diff --git a/crates/swc_css_ast/src/lib.rs b/crates/swc_css_ast/src/lib.rs
index a56d14a9866b..a48d2b0d569a 100644
--- a/crates/swc_css_ast/src/lib.rs
+++ b/crates/swc_css_ast/src/lib.rs
@@ -9,3 +9,26 @@ mod base;
 mod selector;
 mod token;
 mod value;
+
+/// Returns true if the given value matches one of the given patterns.
+///
+/// The type of value and patterns should be identical.
+///
+/// # Exmaples
+///
+/// ```
+/// use swc_atoms::JsWord;
+/// use swc_atoms::js_word;
+/// use swc_css_ast::*;
+///
+/// assert!(matches_eq_ignore_ascii_case!(JsWord::from("A"), js_word!("a")));
+/// assert!(matches_eq_ignore_ascii_case!("A", "a"));
+/// ```
+#[macro_export]
+macro_rules! matches_eq_ignore_ascii_case {
+    ($value:expr, $($pat:expr),*) => {{
+        $(
+            $value.eq_ignore_ascii_case(&$pat) ||
+        )* false
+    }};
+}
diff --git a/crates/swc_css_codegen/src/lib.rs b/crates/swc_css_codegen/src/lib.rs
index 1cdbbc16396a..d0648c1ecaeb 100644
--- a/crates/swc_css_codegen/src/lib.rs
+++ b/crates/swc_css_codegen/src/lib.rs
@@ -1565,7 +1565,7 @@ where
     fn emit_ident(&mut self, n: &Ident) -> Result {
         if self.config.minify {
             let value = if self.ctx.allow_to_lowercase && self.config.minify {
-                n.value.to_lowercase()
+                n.value.to_ascii_lowercase().to_string()
             } else {
                 n.value.to_string()
             };
diff --git a/crates/swc_css_minifier/src/compressor/color.rs b/crates/swc_css_minifier/src/compressor/color.rs
index d2f7011726a7..d6720fc57ab0 100644
--- a/crates/swc_css_minifier/src/compressor/color.rs
+++ b/crates/swc_css_minifier/src/compressor/color.rs
@@ -284,7 +284,7 @@ impl Compressor {
                 Some(*value / 100.0)
             }
             Some(ComponentValue::Ident(box Ident { value, .. }))
-                if value.to_ascii_lowercase() == js_word!("none") =>
+                if value.eq_ignore_ascii_case(&js_word!("none")) =>
             {
                 Some(0.0)
             }
@@ -321,7 +321,7 @@ impl Compressor {
                 Some(value)
             }
             Some(ComponentValue::Ident(box Ident { value, .. }))
-                if value.to_ascii_lowercase() == js_word!("none") =>
+                if value.eq_ignore_ascii_case(&js_word!("none")) =>
             {
                 Some(0.0)
             }
@@ -344,7 +344,7 @@ impl Compressor {
                 Some(*value / 100.0)
             }
             Some(ComponentValue::Ident(box Ident { value, .. }))
-                if value.to_ascii_lowercase() == js_word!("none") =>
+                if value.eq_ignore_ascii_case(&js_word!("none")) =>
             {
                 Some(0.0)
             }
@@ -379,7 +379,7 @@ impl Compressor {
                 Some((2.55 * *value).round())
             }
             Some(ComponentValue::Ident(box Ident { value, .. }))
-                if value.to_ascii_lowercase() == js_word!("none") =>
+                if value.eq_ignore_ascii_case(&js_word!("none")) =>
             {
                 Some(0.0)
             }
diff --git a/crates/swc_css_minifier/src/compressor/declaration.rs b/crates/swc_css_minifier/src/compressor/declaration.rs
index 7bda7d80d493..0245006d5f61 100644
--- a/crates/swc_css_minifier/src/compressor/declaration.rs
+++ b/crates/swc_css_minifier/src/compressor/declaration.rs
@@ -16,34 +16,37 @@ impl Compressor {
                     for value in declaration.value.iter() {
                         match value {
                             outside_node @ ComponentValue::Ident(box Ident { value, .. })
-                                if matches!(
-                                    value.to_ascii_lowercase(),
-                                    js_word!("block") | js_word!("inline") | js_word!("run-in")
+                                if matches_eq_ignore_ascii_case!(
+                                    value,
+                                    js_word!("block"),
+                                    js_word!("inline"),
+                                    js_word!("run-in")
                                 ) =>
                             {
                                 outside = Some(outside_node);
                             }
                             inside_node @ ComponentValue::Ident(box Ident { value, .. })
-                                if matches!(
-                                    value.to_ascii_lowercase(),
-                                    js_word!("flow")
-                                        | js_word!("flow-root")
-                                        | js_word!("table")
-                                        | js_word!("flex")
-                                        | js_word!("grid")
-                                        | js_word!("ruby")
+                                if matches_eq_ignore_ascii_case!(
+                                    value,
+                                    js_word!("flow"),
+                                    js_word!("flow-root"),
+                                    js_word!("table"),
+                                    js_word!("flex"),
+                                    js_word!("grid"),
+                                    js_word!("ruby")
                                 ) =>
                             {
                                 inside = Some(inside_node);
                             }
                             list_item_node @ ComponentValue::Ident(box Ident { value, .. })
-                                if value.to_ascii_lowercase() == js_word!("list-item") =>
+                                if value.eq_ignore_ascii_case(&js_word!("list-item")) =>
                             {
                                 if let Some(ComponentValue::Ident(box Ident { value, .. })) = inside
                                 {
-                                    if !matches!(
-                                        value.to_ascii_lowercase(),
-                                        js_word!("flow") | js_word!("flow-root")
+                                    if !matches_eq_ignore_ascii_case!(
+                                        value,
+                                        js_word!("flow"),
+                                        js_word!("flow-root")
                                     ) {
                                         continue;
                                     }
@@ -66,7 +69,7 @@ impl Compressor {
                                 ..
                             })),
                             None,
-                        ) if inside_value.to_ascii_lowercase() == js_word!("flow") => {
+                        ) if inside_value.eq_ignore_ascii_case(&js_word!("flow")) => {
                             declaration.value = vec![outside.clone()];
                         }
                         // `block flow-root` -> `flow-root`
@@ -82,8 +85,8 @@ impl Compressor {
                                 }),
                             ),
                             None,
-                        ) if outside_value.to_ascii_lowercase() == js_word!("block")
-                            && inside_value.to_ascii_lowercase() == js_word!("flow-root") =>
+                        ) if outside_value.eq_ignore_ascii_case(&js_word!("block"))
+                            && inside_value.eq_ignore_ascii_case(&js_word!("flow-root")) =>
                         {
                             declaration.value = vec![inside.clone()];
                         }
@@ -99,8 +102,8 @@ impl Compressor {
                                 ..
                             })),
                             None,
-                        ) if outside_value.to_ascii_lowercase() == js_word!("inline")
-                            && inside_value.to_ascii_lowercase() == js_word!("flow-root") =>
+                        ) if outside_value.eq_ignore_ascii_case(&js_word!("inline"))
+                            && inside_value.eq_ignore_ascii_case(&js_word!("flow-root")) =>
                         {
                             declaration.value = vec![ComponentValue::Ident(Box::new(Ident {
                                 span: *span,
@@ -119,8 +122,8 @@ impl Compressor {
                                 ..
                             })),
                             Some(list_item),
-                        ) if outside_value.to_ascii_lowercase() == js_word!("block")
-                            && inside_value.to_ascii_lowercase() == js_word!("flow") =>
+                        ) if outside_value.eq_ignore_ascii_case(&js_word!("block"))
+                            && inside_value.eq_ignore_ascii_case(&js_word!("flow")) =>
                         {
                             declaration.value = vec![list_item.clone()];
                         }
@@ -132,7 +135,7 @@ impl Compressor {
                             })),
                             None,
                             Some(list_item),
-                        ) if outside_value.to_ascii_lowercase() == js_word!("block") => {
+                        ) if outside_value.eq_ignore_ascii_case(&js_word!("block")) => {
                             declaration.value = vec![list_item.clone()];
                         }
                         // `flow list-item` -> `list-item`
@@ -143,7 +146,7 @@ impl Compressor {
                                 ..
                             })),
                             Some(list_item),
-                        ) if inside_value.to_ascii_lowercase() == js_word!("flow") => {
+                        ) if inside_value.eq_ignore_ascii_case(&js_word!("flow")) => {
                             declaration.value = vec![list_item.clone()];
                         }
                         // `inline flow list-item` -> `inline list-item`
@@ -159,8 +162,8 @@ impl Compressor {
                                 ..
                             })),
                             Some(list_item),
-                        ) if outside_value.to_ascii_lowercase() == js_word!("inline")
-                            && inside_value.to_ascii_lowercase() == js_word!("flow") =>
+                        ) if outside_value.eq_ignore_ascii_case(&js_word!("inline"))
+                            && inside_value.eq_ignore_ascii_case(&js_word!("flow")) =>
                         {
                             declaration.value = vec![outside.clone(), list_item.clone()];
                         }
@@ -179,10 +182,12 @@ impl Compressor {
                                 }),
                             ),
                             None,
-                        ) if outside_value.to_ascii_lowercase() == js_word!("block")
-                            && matches!(
-                                inside_value.to_ascii_lowercase(),
-                                js_word!("flex") | js_word!("grid") | js_word!("table")
+                        ) if outside_value.eq_ignore_ascii_case(&js_word!("block"))
+                            && matches_eq_ignore_ascii_case!(
+                                inside_value,
+                                js_word!("flex"),
+                                js_word!("grid"),
+                                js_word!("table")
                             ) =>
                         {
                             declaration.value = vec![inside.clone()];
@@ -200,8 +205,8 @@ impl Compressor {
                                 }),
                             ),
                             None,
-                        ) if outside_value.to_ascii_lowercase() == js_word!("inline")
-                            && inside_value.to_ascii_lowercase() == js_word!("ruby") =>
+                        ) if outside_value.eq_ignore_ascii_case(&js_word!("inline"))
+                            && inside_value.eq_ignore_ascii_case(&js_word!("ruby")) =>
                         {
                             declaration.value = vec![inside.clone()];
                         }
@@ -336,7 +341,7 @@ impl Compressor {
                         .into_iter()
                         .map(|node| match node {
                             ComponentValue::Ident(box Ident { value, span, .. })
-                                if value.to_ascii_lowercase() == js_word!("normal") =>
+                                if value.eq_ignore_ascii_case(&js_word!("normal")) =>
                             {
                                 ComponentValue::Number(Box::new(Number {
                                     span,
@@ -345,7 +350,7 @@ impl Compressor {
                                 }))
                             }
                             ComponentValue::Ident(box Ident { value, span, .. })
-                                if value.to_ascii_lowercase() == js_word!("bold") =>
+                                if value.eq_ignore_ascii_case(&js_word!("bold")) =>
                             {
                                 ComponentValue::Number(Box::new(Number {
                                     span,
@@ -464,7 +469,7 @@ impl Compressor {
                                 let value = ident.value.to_ascii_lowercase();
                                 match &*value {
                                     _ if crate::is_css_wide_keyword(&ident.value)
-                                        || ident.value.to_ascii_lowercase() == js_word!("none") =>
+                                        || ident.value.eq_ignore_ascii_case(&js_word!("none")) =>
                                     {
                                         node
                                     }
@@ -512,7 +517,7 @@ impl Compressor {
                     ..
                 }))),
             ) if value_1.value == value_2.value
-                && unit_1.value.to_ascii_lowercase() == unit_2.value.to_ascii_lowercase() =>
+                && unit_1.value.eq_ignore_ascii_case(&unit_2.value) =>
             {
                 true
             }
@@ -552,7 +557,7 @@ impl Compressor {
                     ..
                 }))),
             ) if value_1.value == value_2.value
-                && unit_1.value.to_ascii_lowercase() == unit_2.value.to_ascii_lowercase() =>
+                && unit_1.value.eq_ignore_ascii_case(&unit_2.value) =>
             {
                 true
             }
@@ -586,6 +591,6 @@ impl Compressor {
         matches!((node_1, node_2), (
                  Some(ComponentValue::Ident(box Ident { value: value_1, .. })),
                 Some(ComponentValue::Ident(box Ident { value: value_2, .. })),
-            ) if value_1.to_ascii_lowercase() == value_2.to_ascii_lowercase())
+            ) if value_1.eq_ignore_ascii_case(value_2))
     }
 }
diff --git a/crates/swc_css_minifier/src/compressor/easing_function.rs b/crates/swc_css_minifier/src/compressor/easing_function.rs
index 75c4865bf4d2..e6195ec79807 100644
--- a/crates/swc_css_minifier/src/compressor/easing_function.rs
+++ b/crates/swc_css_minifier/src/compressor/easing_function.rs
@@ -10,7 +10,7 @@ impl Compressor {
                 name,
                 value: function_value,
                 span,
-            }) if name.value.to_ascii_lowercase() == js_word!("cubic-bezier")
+            }) if name.value.eq_ignore_ascii_case(&js_word!("cubic-bezier"))
                 && function_value.len() == 7 =>
             {
                 if let (
@@ -61,7 +61,7 @@ impl Compressor {
                 name,
                 value: function_value,
                 span,
-            }) if name.value.to_ascii_lowercase() == js_word!("steps")
+            }) if name.value.eq_ignore_ascii_case(&js_word!("steps"))
                 && function_value.len() == 3 =>
             {
                 match (&function_value[0], &function_value[2]) {
@@ -95,7 +95,7 @@ impl Compressor {
                         ComponentValue::Ident(box Ident {
                             value: ident_value, ..
                         }),
-                    ) if ident_value.to_ascii_lowercase() == js_word!("jump-start") => {
+                    ) if ident_value.eq_ignore_ascii_case(&js_word!("jump-start")) => {
                         function_value[2] = ComponentValue::Ident(Box::new(Ident {
                             span: *span,
                             value: js_word!("start"),
diff --git a/crates/swc_css_minifier/src/compressor/keyframes.rs b/crates/swc_css_minifier/src/compressor/keyframes.rs
index 5ec5f7477d21..e52f5d03d92c 100644
--- a/crates/swc_css_minifier/src/compressor/keyframes.rs
+++ b/crates/swc_css_minifier/src/compressor/keyframes.rs
@@ -10,7 +10,7 @@ impl Compressor {
         match at_rule.prelude.as_deref() {
             Some(AtRulePrelude::KeyframesPrelude(KeyframesName::Str(string)))
                 if !is_css_wide_keyword(&string.value)
-                    && string.value.to_ascii_lowercase() != js_word!("none") =>
+                    && !string.value.eq_ignore_ascii_case(&js_word!("none")) =>
             {
                 at_rule.prelude = Some(Box::new(AtRulePrelude::KeyframesPrelude(
                     if self.is_ident_shorter_than_str(&string.value) {
@@ -34,7 +34,7 @@ impl Compressor {
 
     pub(super) fn compress_keyframe_selector(&mut self, keyframe_selector: &mut KeyframeSelector) {
         match keyframe_selector {
-            KeyframeSelector::Ident(i) if i.value.to_ascii_lowercase() == js_word!("from") => {
+            KeyframeSelector::Ident(i) if i.value.eq_ignore_ascii_case(&js_word!("from")) => {
                 *keyframe_selector = KeyframeSelector::Percentage(Percentage {
                     span: i.span,
                     value: Number {
diff --git a/crates/swc_css_minifier/src/compressor/math/mod.rs b/crates/swc_css_minifier/src/compressor/math/mod.rs
index 31fb1940b374..34b03b164534 100644
--- a/crates/swc_css_minifier/src/compressor/math/mod.rs
+++ b/crates/swc_css_minifier/src/compressor/math/mod.rs
@@ -2,9 +2,12 @@ use swc_atoms::js_word;
 use swc_css_ast::*;
 
 pub fn is_calc_function_name(ident: &Ident) -> bool {
-    ident.value.to_ascii_lowercase() == js_word!("calc")
-        || ident.value.to_ascii_lowercase() == js_word!("-webkit-calc")
-        || ident.value.to_ascii_lowercase() == js_word!("-moz-calc")
+    matches_eq_ignore_ascii_case!(
+        ident.value,
+        js_word!("calc"),
+        js_word!("-webkit-calc"),
+        js_word!("-moz-calc")
+    )
 }
 
 pub fn transform_calc_value_into_component_value(calc_value: &CalcValue) -> Option<ComponentValue> {
diff --git a/crates/swc_css_minifier/src/compressor/mod.rs b/crates/swc_css_minifier/src/compressor/mod.rs
index 380c11d99beb..3fd7d1686911 100644
--- a/crates/swc_css_minifier/src/compressor/mod.rs
+++ b/crates/swc_css_minifier/src/compressor/mod.rs
@@ -100,19 +100,19 @@ impl VisitMut for Compressor {
 
     fn visit_mut_declaration(&mut self, n: &mut Declaration) {
         if let DeclarationName::Ident(Ident { value, .. }) = &n.name {
-            match value.to_ascii_lowercase() {
-                js_word!("opacity")
-                | js_word!("fill-opacity")
-                | js_word!("stroke-opacity")
-                | js_word!("shape-image-threshold") => {
-                    n.visit_mut_children_with(&mut *self.with_ctx(Ctx {
-                        preserve_alpha_value: false,
-                        ..self.ctx
-                    }));
-                }
-                _ => {
-                    n.visit_mut_children_with(self);
-                }
+            if matches_eq_ignore_ascii_case!(
+                value,
+                js_word!("opacity"),
+                js_word!("fill-opacity"),
+                js_word!("stroke-opacity"),
+                js_word!("shape-image-threshold")
+            ) {
+                n.visit_mut_children_with(&mut *self.with_ctx(Ctx {
+                    preserve_alpha_value: false,
+                    ..self.ctx
+                }));
+            } else {
+                n.visit_mut_children_with(self);
             }
         } else {
             n.visit_mut_children_with(self);
@@ -245,14 +245,14 @@ impl VisitMut for Compressor {
     fn visit_mut_pseudo_class_selector(&mut self, n: &mut PseudoClassSelector) {
         match &n.name {
             Ident { value, .. }
-                if matches!(
-                    value.to_ascii_lowercase(),
-                    js_word!("not")
-                        | js_word!("is")
-                        | js_word!("where")
-                        | js_word!("matches")
-                        | js_word!("-moz-any")
-                        | js_word!("-webkit-any")
+                if matches_eq_ignore_ascii_case!(
+                    value,
+                    js_word!("not"),
+                    js_word!("is"),
+                    js_word!("where"),
+                    js_word!("matches"),
+                    js_word!("-moz-any"),
+                    js_word!("-webkit-any")
                 ) =>
             {
                 n.visit_mut_children_with(&mut *self.with_ctx(Ctx {
@@ -325,23 +325,23 @@ impl VisitMut for Compressor {
     }
 
     fn visit_mut_function(&mut self, n: &mut Function) {
-        match n.name.value.to_ascii_lowercase() {
-            js_word!("rotate")
-            | js_word!("skew")
-            | js_word!("skewx")
-            | js_word!("skewy")
-            | js_word!("rotate3d")
-            | js_word!("rotatex")
-            | js_word!("rotatey")
-            | js_word!("rotatez") => {
-                n.visit_mut_children_with(&mut *self.with_ctx(Ctx {
-                    in_transform_function: true,
-                    ..self.ctx
-                }));
-            }
-            _ => {
-                n.visit_mut_children_with(self);
-            }
+        if matches_eq_ignore_ascii_case!(
+            n.name.value,
+            js_word!("rotate"),
+            js_word!("skew"),
+            js_word!("skewx"),
+            js_word!("skewy"),
+            js_word!("rotate3d"),
+            js_word!("rotatex"),
+            js_word!("rotatey"),
+            js_word!("rotatez")
+        ) {
+            n.visit_mut_children_with(&mut *self.with_ctx(Ctx {
+                in_transform_function: true,
+                ..self.ctx
+            }));
+        } else {
+            n.visit_mut_children_with(self);
         }
     }
 
diff --git a/crates/swc_css_minifier/src/compressor/rules.rs b/crates/swc_css_minifier/src/compressor/rules.rs
index c8b5a83c794d..1d5b69bd6253 100644
--- a/crates/swc_css_minifier/src/compressor/rules.rs
+++ b/crates/swc_css_minifier/src/compressor/rules.rs
@@ -312,14 +312,14 @@ impl Compressor {
             _ => return false,
         };
 
-        match name.to_ascii_lowercase() {
-            js_word!("media")
-            | js_word!("supports")
-            | js_word!("container")
-            | js_word!("layer")
-            | js_word!("nest") => true,
-            _ => false,
-        }
+        matches_eq_ignore_ascii_case!(
+            name,
+            js_word!("media"),
+            js_word!("supports"),
+            js_word!("container"),
+            js_word!("layer"),
+            js_word!("nest")
+        )
     }
 
     fn try_merge_at_rule(&mut self, left: &mut AtRule, right: &mut AtRule) -> Option<AtRule> {
@@ -675,5 +675,5 @@ impl Compressor {
 }
 
 fn need_keep_by_name(name: &JsWord) -> bool {
-    matches!(name.to_ascii_lowercase(), js_word!("color-profile"))
+    matches_eq_ignore_ascii_case!(name, js_word!("color-profile"))
 }
diff --git a/crates/swc_css_minifier/src/compressor/selector.rs b/crates/swc_css_minifier/src/compressor/selector.rs
index e6675e06cf4b..a1ef73f818e7 100644
--- a/crates/swc_css_minifier/src/compressor/selector.rs
+++ b/crates/swc_css_minifier/src/compressor/selector.rs
@@ -63,7 +63,7 @@ impl Compressor {
             }
             // `even` => `2n`
             AnPlusB::Ident(Ident { value, span, .. })
-                if value.to_ascii_lowercase() == js_word!("even") =>
+                if value.eq_ignore_ascii_case(&js_word!("even")) =>
             {
                 *an_plus_b = AnPlusB::AnPlusBNotation(AnPlusBNotation {
                     span: *span,
@@ -110,18 +110,18 @@ impl Compressor {
     pub(super) fn compress_subclass_selector(&mut self, subclass_selector: &mut SubclassSelector) {
         match &subclass_selector {
             SubclassSelector::PseudoElement(PseudoElementSelector { name, span, .. }) => {
-                match name.value.to_ascii_lowercase() {
-                    js_word!("before")
-                    | js_word!("after")
-                    | js_word!("first-letter")
-                    | js_word!("first-line") => {
-                        *subclass_selector = SubclassSelector::PseudoClass(PseudoClassSelector {
-                            span: *span,
-                            name: name.clone(),
-                            children: None,
-                        })
-                    }
-                    _ => {}
+                if matches_eq_ignore_ascii_case!(
+                    name.value,
+                    js_word!("before"),
+                    js_word!("after"),
+                    js_word!("first-letter"),
+                    js_word!("first-line")
+                ) {
+                    *subclass_selector = SubclassSelector::PseudoClass(PseudoClassSelector {
+                        span: *span,
+                        name: name.clone(),
+                        children: None,
+                    })
                 }
             }
             SubclassSelector::PseudoClass(PseudoClassSelector {
@@ -129,7 +129,7 @@ impl Compressor {
                 children: Some(children),
                 span,
                 ..
-            }) if name.value.to_ascii_lowercase() == js_word!("nth-child")
+            }) if name.value.eq_ignore_ascii_case(&js_word!("nth-child"))
                 && children.len() == 1 =>
             {
                 match children.get(0) {
@@ -158,7 +158,9 @@ impl Compressor {
                 children: Some(children),
                 span,
                 ..
-            }) if name.value.to_ascii_lowercase() == js_word!("nth-last-child")
+            }) if name
+                .value
+                .eq_str_ignore_ascii_case(&js_word!("nth-last-child"))
                 && children.len() == 1 =>
             {
                 match children.get(0) {
@@ -187,7 +189,7 @@ impl Compressor {
                 children: Some(children),
                 span,
                 ..
-            }) if name.value.to_ascii_lowercase() == js_word!("nth-of-type")
+            }) if name.value.eq_ignore_ascii_case(&js_word!("nth-of-type"))
                 && children.len() == 1 =>
             {
                 match children.get(0) {
@@ -216,7 +218,9 @@ impl Compressor {
                 children: Some(children),
                 span,
                 ..
-            }) if name.value.to_ascii_lowercase() == js_word!("nth-last-of-type")
+            }) if name
+                .value
+                .eq_ignore_ascii_case(&js_word!("nth-last-of-type"))
                 && children.len() == 1 =>
             {
                 match children.get(0) {
diff --git a/crates/swc_css_minifier/src/compressor/transform_function.rs b/crates/swc_css_minifier/src/compressor/transform_function.rs
index 9e1d9ff3d031..6c06a2dc1c17 100644
--- a/crates/swc_css_minifier/src/compressor/transform_function.rs
+++ b/crates/swc_css_minifier/src/compressor/transform_function.rs
@@ -10,7 +10,7 @@ impl Compressor {
                 name,
                 value: function_value,
                 ..
-            }) if name.value.to_ascii_lowercase() == js_word!("translate")
+            }) if name.value.eq_ignore_ascii_case(&js_word!("translate"))
                 && function_value.len() == 3 =>
             {
                 match (function_value.get(0), function_value.get(2)) {
@@ -44,7 +44,7 @@ impl Compressor {
                 name,
                 value: function_value,
                 ..
-            }) if name.value.to_ascii_lowercase() == js_word!("translate3d")
+            }) if name.value.eq_ignore_ascii_case(&js_word!("translate3d"))
                 && function_value.len() == 5 =>
             {
                 match (
@@ -77,7 +77,7 @@ impl Compressor {
                 name,
                 value: function_value,
                 ..
-            }) if name.value.to_ascii_lowercase() == js_word!("scale")
+            }) if name.value.eq_ignore_ascii_case(&js_word!("scale"))
                 && function_value.len() == 3 =>
             {
                 match (function_value.get(0), function_value.get(2)) {
@@ -130,7 +130,7 @@ impl Compressor {
                 name,
                 value: function_value,
                 ..
-            }) if name.value.to_ascii_lowercase() == js_word!("scale3d")
+            }) if name.value.eq_ignore_ascii_case(&js_word!("scale3d"))
                 && function_value.len() == 5 =>
             {
                 match (
@@ -199,7 +199,7 @@ impl Compressor {
                 name,
                 value: function_value,
                 ..
-            }) if name.value.to_ascii_lowercase() == js_word!("matrix3d")
+            }) if name.value.eq_ignore_ascii_case(&js_word!("matrix3d"))
                 && function_value.len() == 31 =>
             {
                 match (
@@ -314,7 +314,7 @@ impl Compressor {
                 name,
                 value: function_value,
                 ..
-            }) if name.value.to_ascii_lowercase() == js_word!("rotate3d")
+            }) if name.value.eq_ignore_ascii_case(&js_word!("rotate3d"))
                 && function_value.len() == 7 =>
             {
                 match (
@@ -396,7 +396,7 @@ impl Compressor {
                 name,
                 value: function_value,
                 ..
-            }) if name.value.to_ascii_lowercase() == js_word!("rotatez")
+            }) if name.value.eq_ignore_ascii_case(&js_word!("rotatez"))
                 && function_value.len() == 1 =>
             {
                 *name = Ident {
@@ -410,7 +410,7 @@ impl Compressor {
                 name,
                 value: function_value,
                 ..
-            }) if name.value.to_ascii_lowercase() == js_word!("skew")
+            }) if name.value.eq_ignore_ascii_case(&js_word!("skew"))
                 && function_value.len() == 3 =>
             {
                 match (function_value.get(0), function_value.get(2)) {
diff --git a/crates/swc_css_minifier/src/compressor/url.rs b/crates/swc_css_minifier/src/compressor/url.rs
index bda458d731b8..9dbddc670350 100644
--- a/crates/swc_css_minifier/src/compressor/url.rs
+++ b/crates/swc_css_minifier/src/compressor/url.rs
@@ -5,7 +5,7 @@ use super::Compressor;
 
 impl Compressor {
     pub(super) fn compress_url(&self, url: &mut Url) {
-        if url.name.value.to_ascii_lowercase() != js_word!("url") {
+        if !url.name.value.eq_ignore_ascii_case(&js_word!("url")) {
             return;
         }
 
diff --git a/crates/swc_css_minifier/src/lib.rs b/crates/swc_css_minifier/src/lib.rs
index 53bf647ef13f..5d246e243a1c 100644
--- a/crates/swc_css_minifier/src/lib.rs
+++ b/crates/swc_css_minifier/src/lib.rs
@@ -19,15 +19,15 @@ pub fn minify(stylesheet: &mut Stylesheet, _options: MinifyOptions) {
 
 #[inline]
 fn is_css_wide_keyword(ident: &JsWord) -> bool {
-    match ident.to_ascii_lowercase() {
+    matches_eq_ignore_ascii_case!(
+        ident,
         // CSS Values and Units Level 3: https://drafts.csswg.org/css-values-3/#common-keywords
-        |  js_word!("initial")
-        |  js_word!("inherit")
-        |  js_word!("unset")
-        |  js_word!("default")
+        js_word!("initial"),
+        js_word!("inherit"),
+        js_word!("unset"),
+        js_word!("default"),
         // CSS Cascading and Inheritance Level 5: https://drafts.csswg.org/css-cascade-5/#defaulting-keywords
-        |  js_word!("revert")
-        |  js_word!("revert-layer") => true,
-        _ => false
-    }
+        js_word!("revert"),
+        js_word!("revert-layer")
+    )
 }
diff --git a/crates/swc_css_parser/src/lexer/mod.rs b/crates/swc_css_parser/src/lexer/mod.rs
index 4d1441406771..8a4778723b0d 100644
--- a/crates/swc_css_parser/src/lexer/mod.rs
+++ b/crates/swc_css_parser/src/lexer/mod.rs
@@ -2,7 +2,7 @@ use std::{cell::RefCell, char::REPLACEMENT_CHARACTER, rc::Rc};
 
 use swc_atoms::{js_word, Atom, JsWord};
 use swc_common::{input::Input, BytePos, Span};
-use swc_css_ast::{DimensionToken, NumberType, Token, TokenAndSpan};
+use swc_css_ast::{matches_eq_ignore_ascii_case, DimensionToken, NumberType, Token, TokenAndSpan};
 
 use crate::{
     error::{Error, ErrorKind},
@@ -566,7 +566,9 @@ where
 
         // If string’s value is an ASCII case-insensitive match for "url", and the next
         // input code point is U+0028 LEFT PARENTHESIS ((), consume it.
-        if ident_sequence.0.to_ascii_lowercase() == js_word!("url") && self.next() == Some('(') {
+        if matches_eq_ignore_ascii_case!(ident_sequence.0, js_word!("url"))
+            && self.next() == Some('(')
+        {
             self.consume();
 
             let start_whitespace = self.input.last_pos();
diff --git a/crates/swc_css_parser/src/parser/at_rules/mod.rs b/crates/swc_css_parser/src/parser/at_rules/mod.rs
index be522e1975c8..e4e9b4ae744d 100644
--- a/crates/swc_css_parser/src/parser/at_rules/mod.rs
+++ b/crates/swc_css_parser/src/parser/at_rules/mod.rs
@@ -175,7 +175,9 @@ where
 
                 let layer_name = if !is!(self, EOF) {
                     match cur!(self) {
-                        Token::Ident { value, .. } if *value.to_ascii_lowercase() == *"layer" => {
+                        Token::Ident { value, .. }
+                            if matches_eq_ignore_ascii_case!(value, js_word!("layer")) =>
+                        {
                             let name = ImportLayerName::Ident(self.parse()?);
 
                             self.input.skip_ws();
@@ -183,7 +185,7 @@ where
                             Some(Box::new(name))
                         }
                         Token::Function { value, .. }
-                            if *value.to_ascii_lowercase() == *"layer" =>
+                            if matches_eq_ignore_ascii_case!(value, js_word!("layer")) =>
                         {
                             let ctx = Ctx {
                                 in_import_at_rule: true,
@@ -772,7 +774,9 @@ where
 
         let supports = if !is!(self, EOF) {
             match cur!(self) {
-                Token::Function { value, .. } if *value.to_ascii_lowercase() == *"supports" => {
+                Token::Function { value, .. }
+                    if matches_eq_ignore_ascii_case!(value, js_word!("supports")) =>
+                {
                     let ctx = Ctx {
                         in_import_at_rule: true,
                         ..self.ctx
@@ -820,8 +824,11 @@ where
 
                 match cur!(self) {
                     Token::Function { value, .. }
-                        if (&*value.to_ascii_lowercase() == "local"
-                            || &*value.to_ascii_lowercase() == "global") =>
+                        if matches_eq_ignore_ascii_case!(
+                            value,
+                            js_word!("local"),
+                            js_word!("global")
+                        ) =>
                     {
                         let span = self.input.cur_span();
                         let pseudo = match bump!(self) {
@@ -852,8 +859,11 @@ where
                         )))
                     }
                     Token::Ident { value, .. }
-                        if (&*value.to_ascii_lowercase() == "local"
-                            || &*value.to_ascii_lowercase() == "global") =>
+                        if matches_eq_ignore_ascii_case!(
+                            value,
+                            js_word!("local"),
+                            js_word!("global")
+                        ) =>
                     {
                         let pseudo = self.parse()?;
 
@@ -882,7 +892,7 @@ where
             tok!("ident") => {
                 let custom_ident: CustomIdent = self.parse()?;
 
-                if &*custom_ident.value.to_ascii_lowercase() == "none" {
+                if matches_eq_ignore_ascii_case!(custom_ident.value, js_word!("none")) {
                     return Err(Error::new(
                         custom_ident.span,
                         ErrorKind::InvalidCustomIdent(custom_ident.value),
@@ -1176,7 +1186,9 @@ where
 
                 Ok(SupportsFeature::Declaration(Box::new(declaration)))
             }
-            Token::Function { value, .. } if &*value.to_ascii_lowercase() == "selector" => {
+            Token::Function { value, .. }
+                if matches_eq_ignore_ascii_case!(&**value, "selector") =>
+            {
                 // TODO improve me
                 let ctx = Ctx {
                     in_supports_at_rule: true,
@@ -1280,9 +1292,7 @@ where
                 value: function_name,
                 ..
             } => {
-                if &*function_name.to_ascii_lowercase() == "url"
-                    || &*function_name.to_ascii_lowercase() == "src"
-                {
+                if matches_eq_ignore_ascii_case!(function_name, js_word!("url"), js_word!("src")) {
                     Ok(DocumentPreludeMatchingFunction::Url(self.parse()?))
                 } else {
                     // TODO improve me
@@ -1985,10 +1995,7 @@ where
 
         let value = match cur!(self) {
             Token::Ident { value, .. }
-                if matches!(
-                    &*value.to_ascii_lowercase(),
-                    "left" | "right" | "first" | "blank"
-                ) =>
+                if matches_eq_ignore_ascii_case!(&**value, "left", "right", "first", "blank") =>
             {
                 self.parse()?
             }
diff --git a/crates/swc_css_parser/src/parser/macros.rs b/crates/swc_css_parser/src/parser/macros.rs
index c8cccfe9837f..0283fd2366d1 100644
--- a/crates/swc_css_parser/src/parser/macros.rs
+++ b/crates/swc_css_parser/src/parser/macros.rs
@@ -73,7 +73,7 @@ macro_rules! is_case_insensitive_ident {
     ($parser:expr, $tt:tt) => {{
         match $parser.input.cur() {
             Some(swc_css_ast::Token::Ident { value, .. })
-                if &*value.to_ascii_lowercase() == $tt =>
+                if (&**value).eq_ignore_ascii_case($tt) =>
             {
                 true
             }
@@ -86,9 +86,7 @@ macro_rules! is_one_of_case_insensitive_ident {
     ($parser:expr, $($tt:tt),+) => {
         match $parser.input.cur() {
             Some(swc_css_ast::Token::Ident { value, .. }) => {
-                let lowercased = &*value.to_ascii_lowercase();
-
-                if $(lowercased == $tt)||* {
+                if $((&**value).eq_ignore_ascii_case($tt))||* {
                     true
                 } else {
                     false
diff --git a/crates/swc_css_parser/src/parser/selectors/mod.rs b/crates/swc_css_parser/src/parser/selectors/mod.rs
index c318e09c38e5..79e14373bc39 100644
--- a/crates/swc_css_parser/src/parser/selectors/mod.rs
+++ b/crates/swc_css_parser/src/parser/selectors/mod.rs
@@ -1,3 +1,4 @@
+use swc_atoms::js_word;
 use swc_common::{BytePos, Span, Spanned};
 use swc_css_ast::*;
 
@@ -1187,8 +1188,7 @@ where
         match cur!(self) {
             //  odd | even
             Token::Ident { value, .. }
-            if &(*value).to_ascii_lowercase() == "odd"
-                || &(*value).to_ascii_lowercase() == "even" =>
+                if matches_eq_ignore_ascii_case!(value, js_word!("odd"), js_word!("even")) =>
                 {
                     Ok(AnPlusB::Ident(self.parse()?))
                 }
diff --git a/crates/swc_css_parser/src/parser/syntax/mod.rs b/crates/swc_css_parser/src/parser/syntax/mod.rs
index ba67b45fbdb7..9efae7729416 100644
--- a/crates/swc_css_parser/src/parser/syntax/mod.rs
+++ b/crates/swc_css_parser/src/parser/syntax/mod.rs
@@ -692,7 +692,7 @@ where
                         ..
                     },
                 ) if exclamation_point_span.is_some()
-                    && value.to_ascii_lowercase() == js_word!("important") =>
+                    && matches_eq_ignore_ascii_case!(value, js_word!("important")) =>
                 {
                     important_ident = Some(token_and_span.clone());
                 }
diff --git a/crates/swc_css_parser/src/parser/values_and_units/mod.rs b/crates/swc_css_parser/src/parser/values_and_units/mod.rs
index d5566b6be551..3727f25adf11 100644
--- a/crates/swc_css_parser/src/parser/values_and_units/mod.rs
+++ b/crates/swc_css_parser/src/parser/values_and_units/mod.rs
@@ -78,7 +78,7 @@ where
             Token::Ident { value, .. } => {
                 if value.starts_with("--") {
                     return Ok(ComponentValue::DashedIdent(self.parse()?));
-                } else if &*value.to_ascii_lowercase() == "u"
+                } else if matches_eq_ignore_ascii_case!(value, js_word!("u"))
                     && peeked_is_one_of!(self, "+", "number", "dimension")
                 {
                     return Ok(ComponentValue::UnicodeRange(self.parse()?));
@@ -371,7 +371,9 @@ where
                 let mut is_legacy_syntax = true;
 
                 match cur!(self) {
-                    Token::Ident { value, .. } if &*value.to_ascii_lowercase() == "from" => {
+                    Token::Ident { value, .. }
+                        if matches_eq_ignore_ascii_case!(value, js_word!("from")) =>
+                    {
                         is_legacy_syntax = false;
 
                         values.push(ComponentValue::Ident(self.parse()?));
@@ -806,7 +808,7 @@ where
 
                 match cur!(self) {
                     Token::Ident { value, .. }
-                        if &*value.to_ascii_lowercase() == "from"
+                        if matches_eq_ignore_ascii_case!(value, js_word!("from"))
                             && function_name != "device-cmyk" =>
                     {
                         values.push(ComponentValue::Ident(self.parse()?));
@@ -1282,7 +1284,9 @@ where
                 let mut has_variable = false;
 
                 match cur!(self) {
-                    Token::Ident { value, .. } if &*value.to_ascii_lowercase() == "from" => {
+                    Token::Ident { value, .. }
+                        if matches_eq_ignore_ascii_case!(value, js_word!("from")) =>
+                    {
                         values.push(ComponentValue::Ident(self.parse()?));
 
                         self.input.skip_ws();
@@ -1312,15 +1316,16 @@ where
 
                                 Ok(Some(ComponentValue::DashedIdent(parser.parse()?)))
                             } else {
-                                match &*value.to_ascii_lowercase() {
-                                    "xyz" | "xyz-d50" | "xyz-d65" => is_xyz = true,
-                                    _ => {
-                                        // There are predefined-rgb-params , but
-                                        // For unknown, we don't return an error
-                                        // to
-                                        // continue to support invalid color,
-                                        // because they fallback in browser
-                                    }
+                                if matches_eq_ignore_ascii_case!(
+                                    &**value, "xyz", "xyz-d50", "xyz-d65"
+                                ) {
+                                    is_xyz = true
+                                } else {
+                                    // There are predefined-rgb-params , but
+                                    // For unknown, we don't return an error
+                                    // to
+                                    // continue to support invalid color,
+                                    // because they fallback in browser
                                 }
 
                                 Ok(Some(ComponentValue::Ident(parser.parse()?)))
@@ -1397,9 +1402,8 @@ where
                             }
                             Token::Function { value, .. }
                                 if is_math_function(value)
-                                    || matches!(
-                                        &*value.to_ascii_lowercase(),
-                                        "var" | "env" | "constant"
+                                    || matches_eq_ignore_ascii_case!(
+                                        &**value, "var", "env", "constant"
                                     ) =>
                             {
                                 ComponentValue::Function(self.parse()?)
@@ -1674,7 +1678,7 @@ where
 
         match cur!(self) {
             Token::Function { value, .. }
-                if matches!(&*value.to_ascii_lowercase(), "var" | "env" | "constant") =>
+                if matches_eq_ignore_ascii_case!(&**value, "var", "env", "constant") =>
             {
                 *has_before_variable = true;
 
@@ -1807,11 +1811,10 @@ where
 
         match bump!(self) {
             Token::Ident { value, raw, .. } => {
-                match &*value.to_ascii_lowercase() {
-                    "initial" | "inherit" | "unset" | "revert" | "default" => {
-                        return Err(Error::new(span, ErrorKind::InvalidCustomIdent(value)));
-                    }
-                    _ => {}
+                if matches_eq_ignore_ascii_case!(
+                    &*value, "initial", "inherit", "unset", "revert", "default"
+                ) {
+                    return Err(Error::new(span, ErrorKind::InvalidCustomIdent(value)));
                 }
 
                 Ok(CustomIdent {
@@ -2564,9 +2567,7 @@ where
                 value: function_name,
                 raw: raw_function_name,
             } => {
-                if &*function_name.to_ascii_lowercase() != "url"
-                    && &*function_name.to_ascii_lowercase() != "src"
-                {
+                if !matches_eq_ignore_ascii_case!(function_name, js_word!("url"), js_word!("src")) {
                     return Err(Error::new(
                         span,
                         ErrorKind::Expected("'url' or 'src' name of a function token"),
@@ -2645,7 +2646,7 @@ where
 
         // should start with `u` or `U`
         match cur!(self) {
-            Token::Ident { value, .. } if &*value.to_ascii_lowercase() == "u" => {
+            Token::Ident { value, .. } if matches_eq_ignore_ascii_case!(value, js_word!("u")) => {
                 let ident = match bump!(self) {
                     Token::Ident { value, .. } => value,
                     _ => {
@@ -3604,28 +3605,25 @@ fn is_length_unit(unit: &str) -> bool {
 }
 
 fn is_container_lengths_unit(unit: &str) -> bool {
-    matches!(
-        &*unit.to_ascii_lowercase(),
-        "cqw" | "cqh" | "cqi" | "cqb" | "cqmin" | "cqmax"
-    )
+    matches_eq_ignore_ascii_case!(unit, "cqw", "cqh", "cqi", "cqb", "cqmin", "cqmax")
 }
 
 fn is_angle_unit(unit: &str) -> bool {
-    matches!(&*unit.to_ascii_lowercase(), "deg" | "grad" | "rad" | "turn")
+    matches_eq_ignore_ascii_case!(unit, "deg", "grad", "rad", "turn")
 }
 
 fn is_time_unit(unit: &str) -> bool {
-    matches!(&*unit.to_ascii_lowercase(), "s" | "ms")
+    matches_eq_ignore_ascii_case!(unit, "s", "ms")
 }
 
 fn is_frequency_unit(unit: &str) -> bool {
-    matches!(&*unit.to_ascii_lowercase(), "hz" | "khz")
+    matches_eq_ignore_ascii_case!(unit, "hz", "khz")
 }
 
 fn is_resolution_unit(unit: &str) -> bool {
-    matches!(&*unit.to_ascii_lowercase(), "dpi" | "dpcm" | "dppx" | "x")
+    matches_eq_ignore_ascii_case!(unit, "dpi", "dpcm", "dppx", "x")
 }
 
 fn is_flex_unit(unit: &str) -> bool {
-    matches!(&*unit.to_ascii_lowercase(), "fr")
+    matches_eq_ignore_ascii_case!(unit, "fr")
 }
diff --git a/crates/swc_css_prefixer/src/prefixer.rs b/crates/swc_css_prefixer/src/prefixer.rs
index e2ab9db30a7d..2ed9691b44ae 100644
--- a/crates/swc_css_prefixer/src/prefixer.rs
+++ b/crates/swc_css_prefixer/src/prefixer.rs
@@ -127,7 +127,7 @@ impl VisitMut for CrossFadeFunctionReplacerOnLegacyVariant<'_> {
     fn visit_mut_function(&mut self, n: &mut Function) {
         n.visit_mut_children_with(self);
 
-        if &*n.name.value.to_lowercase() == self.from {
+        if n.name.value.eq_str_ignore_ascii_case(self.from) {
             let mut transparency_values = vec![];
 
             for group in n.value.split_mut(|n| {
@@ -269,7 +269,7 @@ impl VisitMut for ImageSetFunctionReplacerOnLegacyVariant<'_> {
 
         n.visit_mut_children_with(self);
 
-        if &*n.name.value.to_lowercase() == self.from {
+        if n.name.value.eq_str_ignore_ascii_case(self.from) {
             n.name.value = self.to.into();
             n.name.raw = None;
         }
@@ -300,7 +300,7 @@ impl VisitMut for LinearGradientFunctionReplacerOnLegacyVariant<'_> {
     fn visit_mut_function(&mut self, n: &mut Function) {
         n.visit_mut_children_with(self);
 
-        if &*n.name.value.to_lowercase() == self.from {
+        if &*n.name.value.to_ascii_lowercase() == self.from {
             n.name.value = self.to.into();
             n.name.raw = None;
 
@@ -485,14 +485,14 @@ impl VisitMut for MediaFeatureResolutionReplacerOnLegacyVariant<'_> {
                 ..
             }) = &n.name;
 
-            if &*feature_name_value.to_lowercase() == self.from {
+            if &*feature_name_value.to_ascii_lowercase() == self.from {
                 n.name = MediaFeatureName::Ident(Ident {
                     span: *feature_name_span,
                     value: self.to.into(),
                     raw: None,
                 });
 
-                let left = match &*resolution_unit.value.to_lowercase() {
+                let left = match &*resolution_unit.value.to_ascii_lowercase() {
                     "dpi" => (resolution_value.value / 96.0 * 100.0).round() / 100.0,
                     "dpcm" => (((resolution_value.value * 2.54) / 96.0) * 100.0).round() / 100.0,
                     _ => resolution_value.value,
@@ -1472,7 +1472,7 @@ impl VisitMut for Prefixer {
             }};
         }
 
-        let property_name = &*name.to_lowercase();
+        let property_name = &*name.to_ascii_lowercase();
 
         match property_name {
             "appearance" => {
@@ -1484,7 +1484,7 @@ impl VisitMut for Prefixer {
             "animation" => {
                 let need_prefix = n.value.iter().all(|n| match n {
                     ComponentValue::Ident(ident) => !matches!(
-                        &*ident.value.to_lowercase(),
+                        &*ident.value.to_ascii_lowercase(),
                         "reverse" | "alternate-reverse"
                     ),
                     _ => true,
@@ -1517,7 +1517,7 @@ impl VisitMut for Prefixer {
 
             "animation-direction" => {
                 if let ComponentValue::Ident(ident) = &n.value[0] {
-                    match &*ident.value.to_lowercase() {
+                    match &*ident.value.to_ascii_lowercase() {
                         "alternate-reverse" | "reverse" => {}
                         _ => {
                             add_declaration!(Prefix::Webkit, "-webkit-animation-direction", None);
@@ -1554,7 +1554,7 @@ impl VisitMut for Prefixer {
 
             "background-clip" => {
                 if let ComponentValue::Ident(ident) = &n.value[0] {
-                    if &*ident.value.to_lowercase() == "text" {
+                    if &*ident.value.to_ascii_lowercase() == "text" {
                         add_declaration!(Prefix::Webkit, "-webkit-background-clip", None);
                     }
                 }
@@ -1886,7 +1886,7 @@ impl VisitMut for Prefixer {
             "flex-flow" => {
                 let is_single_flex_wrap = matches!(n.value.get(0), Some(ComponentValue::Ident(box Ident { value, .. })) if n.value.len() == 1
                 && matches!(
-                    &*value.to_lowercase(),
+                    &*value.to_ascii_lowercase(),
                     "wrap" | "nowrap" | "wrap-reverse"
                 ));
 
@@ -2313,7 +2313,7 @@ impl VisitMut for Prefixer {
                 add_declaration!(Prefix::Moz, "-moz-user-select", None);
 
                 if let ComponentValue::Ident(ident) = &n.value[0] {
-                    match &*ident.value.to_lowercase() {
+                    match &*ident.value.to_ascii_lowercase() {
                         "contain" => {
                             add_declaration!(
                                 Prefix::Ms,
@@ -2335,18 +2335,18 @@ impl VisitMut for Prefixer {
 
                 let has_3d_function = n.value.iter().any(|n| match n {
                     ComponentValue::Function(function)
-                        if matches!(
-                            &*function.name.value.to_ascii_lowercase(),
-                            "matrix3d"
-                                | "translate3d"
-                                | "translatez"
-                                | "scale3d"
-                                | "scalez"
-                                | "rotate3d"
-                                | "rotatex"
-                                | "rotatey"
-                                | "rotatez"
-                                | "perspective"
+                        if matches_eq_ignore_ascii_case!(
+                            &*function.name.value,
+                            "matrix3d",
+                            "translate3d",
+                            "translatez",
+                            "scale3d",
+                            "scalez",
+                            "rotate3d",
+                            "rotatex",
+                            "rotatey",
+                            "rotatez",
+                            "perspective"
                         ) =>
                     {
                         true
@@ -2394,7 +2394,7 @@ impl VisitMut for Prefixer {
                     match &n.value[0] {
                         ComponentValue::Ident(ident)
                             if matches!(
-                                &*ident.value.to_lowercase(),
+                                &*ident.value.to_ascii_lowercase(),
                                 "none"
                                     | "underline"
                                     | "overline"
@@ -2437,7 +2437,7 @@ impl VisitMut for Prefixer {
 
             "text-decoration-skip-ink" => {
                 if let ComponentValue::Ident(ident) = &n.value[0] {
-                    match &*ident.value.to_lowercase() {
+                    match &*ident.value.to_ascii_lowercase() {
                         "auto" => {
                             add_declaration!(
                                 Prefix::Webkit,
@@ -2458,7 +2458,7 @@ impl VisitMut for Prefixer {
 
             "text-size-adjust" if n.value.len() == 1 => {
                 if let ComponentValue::Ident(ident) = &n.value[0] {
-                    if &*ident.value.to_lowercase() == "none" {
+                    if &*ident.value.to_ascii_lowercase() == "none" {
                         add_declaration!(Prefix::Webkit, "-webkit-text-size-adjust", None);
                         add_declaration!(Prefix::Moz, "-moz-text-size-adjust", None);
                         add_declaration!(Prefix::Ms, "-ms-text-size-adjust", None);
@@ -2565,7 +2565,7 @@ impl VisitMut for Prefixer {
                 };
 
                 if let ComponentValue::Ident(ident) = &n.value[0] {
-                    match &*ident.value.to_lowercase() {
+                    match &*ident.value.to_ascii_lowercase() {
                         "vertical-lr" => {
                             add_declaration!(Prefix::Webkit, "-webkit-writing-mode", None);
 
@@ -2935,7 +2935,7 @@ impl VisitMut for Prefixer {
 
             "overscroll-behavior" => {
                 if let ComponentValue::Ident(ident) = &n.value[0] {
-                    match &*ident.value.to_lowercase() {
+                    match &*ident.value.to_ascii_lowercase() {
                         "auto" => {
                             add_declaration!(
                                 Prefix::Ms,
@@ -2970,7 +2970,7 @@ impl VisitMut for Prefixer {
 
             "break-inside" => {
                 if let ComponentValue::Ident(ident) = &n.value[0] {
-                    match &*ident.value.to_lowercase() {
+                    match &*ident.value.to_ascii_lowercase() {
                         "auto" | "avoid" => {
                             add_declaration!(Prefix::Webkit, "-webkit-column-break-inside", None);
                         }
@@ -2981,7 +2981,7 @@ impl VisitMut for Prefixer {
 
             "break-before" => {
                 if let ComponentValue::Ident(ident) = &n.value[0] {
-                    match &*ident.value.to_lowercase() {
+                    match &*ident.value.to_ascii_lowercase() {
                         "auto" | "avoid" => {
                             add_declaration!(Prefix::Webkit, "-webkit-column-break-before", None);
                         }
@@ -2999,7 +2999,7 @@ impl VisitMut for Prefixer {
 
             "break-after" => {
                 if let ComponentValue::Ident(ident) = &n.value[0] {
-                    match &*ident.value.to_lowercase() {
+                    match &*ident.value.to_ascii_lowercase() {
                         "auto" | "avoid" => {
                             add_declaration!(Prefix::Webkit, "-webkit-column-break-after", None);
                         }
diff --git a/crates/swc_css_utils/src/lib.rs b/crates/swc_css_utils/src/lib.rs
index b12c8ba8b373..7ee85a1c1b4b 100644
--- a/crates/swc_css_utils/src/lib.rs
+++ b/crates/swc_css_utils/src/lib.rs
@@ -18,7 +18,7 @@ impl VisitMut for IdentReplacer<'_> {
     fn visit_mut_ident(&mut self, n: &mut Ident) {
         n.visit_mut_children_with(self);
 
-        if &*n.value.to_lowercase() == self.from {
+        if n.value.eq_str_ignore_ascii_case(self.from) {
             n.value = self.to.into();
             n.raw = None;
         }
@@ -41,7 +41,7 @@ impl VisitMut for FunctionNameReplacer<'_> {
     fn visit_mut_function(&mut self, n: &mut Function) {
         n.visit_mut_children_with(self);
 
-        if &*n.name.value.to_lowercase() == self.from {
+        if n.name.value.eq_str_ignore_ascii_case(self.from) {
             n.name.value = self.to.into();
             n.name.raw = None;
         }
@@ -64,7 +64,7 @@ impl VisitMut for PseudoClassSelectorNameReplacer<'_> {
     fn visit_mut_pseudo_class_selector(&mut self, n: &mut PseudoClassSelector) {
         n.visit_mut_children_with(self);
 
-        if &*n.name.value.to_lowercase() == self.from {
+        if n.name.value.eq_str_ignore_ascii_case(self.from) {
             n.name.value = self.to.into();
             n.name.raw = None;
         }
@@ -87,7 +87,7 @@ impl VisitMut for PseudoElementSelectorNameReplacer<'_> {
     fn visit_mut_pseudo_element_selector(&mut self, n: &mut PseudoElementSelector) {
         n.visit_mut_children_with(self);
 
-        if &*n.name.value.to_lowercase() == self.from {
+        if n.name.value.eq_str_ignore_ascii_case(self.from) {
             n.name.value = self.to.into();
             n.name.raw = None;
         }
@@ -112,7 +112,7 @@ impl VisitMut for PseudoElementOnPseudoClassReplacer<'_> {
 
         match n {
             SubclassSelector::PseudoElement(PseudoElementSelector { name, span, .. })
-                if &*name.value.to_lowercase() == self.from =>
+                if name.value.eq_str_ignore_ascii_case(self.from) =>
             {
                 *n = SubclassSelector::PseudoClass(PseudoClassSelector {
                     span: *span,