diff --git a/src/Illuminate/Database/Eloquent/Concerns/HasAttributes.php b/src/Illuminate/Database/Eloquent/Concerns/HasAttributes.php
index d5f8225cf1bc..557a36b90448 100644
--- a/src/Illuminate/Database/Eloquent/Concerns/HasAttributes.php
+++ b/src/Illuminate/Database/Eloquent/Concerns/HasAttributes.php
@@ -165,6 +165,13 @@ trait HasAttributes
      */
     protected static $setAttributeMutatorCache = [];
 
+    /**
+     * The cache of the converted cast types.
+     *
+     * @var array
+     */
+    protected static $castTypeCache = [];
+
     /**
      * The encrypter instance that is used to encrypt attributes.
      *
@@ -818,19 +825,23 @@ protected function getEnumCastableAttributeValue($key, $value)
      */
     protected function getCastType($key)
     {
-        if ($this->isCustomDateTimeCast($this->getCasts()[$key])) {
-            return 'custom_datetime';
-        }
+        $castType = $this->getCasts()[$key];
 
-        if ($this->isImmutableCustomDateTimeCast($this->getCasts()[$key])) {
-            return 'immutable_custom_datetime';
+        if (isset(static::$castTypeCache[$castType])) {
+            return static::$castTypeCache[$castType];
         }
 
-        if ($this->isDecimalCast($this->getCasts()[$key])) {
-            return 'decimal';
+        if ($this->isCustomDateTimeCast($castType)) {
+            $convertedCastType = 'custom_datetime';
+        } elseif ($this->isImmutableCustomDateTimeCast($castType)) {
+            $convertedCastType = 'immutable_custom_datetime';
+        } elseif ($this->isDecimalCast($castType)) {
+            $convertedCastType = 'decimal';
+        } else {
+            $convertedCastType = trim(strtolower($castType));
         }
 
-        return trim(strtolower($this->getCasts()[$key]));
+        return static::$castTypeCache[$castType] = $convertedCastType;
     }
 
     /**
@@ -882,8 +893,8 @@ protected function isCustomDateTimeCast($cast)
      */
     protected function isImmutableCustomDateTimeCast($cast)
     {
-        return strncmp($cast, 'immutable_date:', 15) === 0 ||
-               strncmp($cast, 'immutable_datetime:', 19) === 0;
+        return str_starts_with($cast, 'immutable_date:') ||
+                str_starts_with($cast, 'immutable_datetime:');
     }
 
     /**
@@ -1491,11 +1502,13 @@ protected function isEncryptedCastable($key)
      */
     protected function isClassCastable($key)
     {
-        if (! array_key_exists($key, $this->getCasts())) {
+        $casts = $this->getCasts();
+
+        if (! array_key_exists($key, $casts)) {
             return false;
         }
 
-        $castType = $this->parseCasterClass($this->getCasts()[$key]);
+        $castType = $this->parseCasterClass($casts[$key]);
 
         if (in_array($castType, static::$primitiveCastTypes)) {
             return false;
@@ -1516,11 +1529,13 @@ protected function isClassCastable($key)
      */
     protected function isEnumCastable($key)
     {
-        if (! array_key_exists($key, $this->getCasts())) {
+        $casts = $this->getCasts();
+
+        if (! array_key_exists($key, $casts)) {
             return false;
         }
 
-        $castType = $this->getCasts()[$key];
+        $castType = $casts[$key];
 
         if (in_array($castType, static::$primitiveCastTypes)) {
             return false;