diff --git a/packages/core/useElementSize/demo.vue b/packages/core/useElementSize/demo.vue
index 49aa3148939..14a76688696 100644
--- a/packages/core/useElementSize/demo.vue
+++ b/packages/core/useElementSize/demo.vue
@@ -4,7 +4,13 @@ import { stringify } from '@vueuse/docs-utils'
 import { useElementSize } from '@vueuse/core'
 
 const el = ref(null)
-const size = reactive(useElementSize(el))
+const size = reactive(
+  useElementSize(
+    el,
+    { width: 0, height: 0 },
+    { box: 'border-box' },
+  ),
+)
 const text = stringify(size)
 </script>
 
diff --git a/packages/core/useElementSize/index.ts b/packages/core/useElementSize/index.ts
index fc940e958db..32d313dffd5 100644
--- a/packages/core/useElementSize/index.ts
+++ b/packages/core/useElementSize/index.ts
@@ -22,21 +22,40 @@ export function useElementSize(
   initialSize: ElementSize = { width: 0, height: 0 },
   options: UseResizeObserverOptions = {},
 ) {
+  const { box = 'content-box' } = options
   const width = ref(initialSize.width)
   const height = ref(initialSize.height)
 
   useResizeObserver(
     target,
     ([entry]) => {
-      width.value = entry.contentRect.width
-      height.value = entry.contentRect.height
+      const boxSize = box === 'border-box'
+        ? entry.borderBoxSize
+        : box === 'content-box'
+          ? entry.contentBoxSize
+          : entry.devicePixelContentBoxSize
+
+      if (boxSize) {
+        width.value = boxSize.reduce((acc, { inlineSize }) => acc + inlineSize, 0)
+        height.value = boxSize.reduce((acc, { blockSize }) => acc + blockSize, 0)
+      }
+      else {
+        // fallback
+        width.value = entry.contentRect.width
+        height.value = entry.contentRect.height
+      }
     },
     options,
   )
-  watch(() => unrefElement(target), (ele) => {
-    width.value = ele ? initialSize.width : 0
-    height.value = ele ? initialSize.height : 0
-  })
+
+  watch(
+    () => unrefElement(target),
+    (ele) => {
+      width.value = ele ? initialSize.width : 0
+      height.value = ele ? initialSize.height : 0
+    },
+  )
+
   return {
     width,
     height,
diff --git a/packages/core/useResizeObserver/index.ts b/packages/core/useResizeObserver/index.ts
index 2acb815e2c8..c4681371011 100644
--- a/packages/core/useResizeObserver/index.ts
+++ b/packages/core/useResizeObserver/index.ts
@@ -24,11 +24,11 @@ export type ResizeObserverCallback = (entries: ReadonlyArray<ResizeObserverEntry
 export interface UseResizeObserverOptions extends ConfigurableWindow {
   /**
    * Sets which box model the observer will observe changes to. Possible values
-   * are `content-box` (the default), and `border-box`.
+   * are `content-box` (the default), `border-box` and `device-pixel-content-box`.
    *
    * @default 'content-box'
    */
-  box?: 'content-box' | 'border-box'
+  box?: ResizeObserverBoxOptions
 }
 
 declare class ResizeObserver {