diff --git a/system/Validation/FormatRules.php b/system/Validation/FormatRules.php
index 3aa1c6840ceb..ad41150a8c13 100644
--- a/system/Validation/FormatRules.php
+++ b/system/Validation/FormatRules.php
@@ -128,10 +128,12 @@ public function hex(?string $str = null): bool
 
     /**
      * Integer
+     *
+     * @param int|null $str
      */
-    public function integer(?string $str = null): bool
+    public function integer($str = null): bool
     {
-        return (bool) preg_match('/\A[\-+]?\d+\z/', $str ?? '');
+        return is_int($str);
     }
 
     /**
@@ -155,8 +157,7 @@ public function is_natural_no_zero(?string $str = null): bool
      */
     public function numeric(?string $str = null): bool
     {
-        // @see https://regex101.com/r/bb9wtr/2
-        return (bool) preg_match('/\A[\-+]?\d*\.?\d+\z/', $str ?? '');
+        return is_numeric($str);
     }
 
     /**
diff --git a/system/Validation/StrictRules/FormatRules.php b/system/Validation/StrictRules/FormatRules.php
index 97df6c04aecb..18a140342b35 100644
--- a/system/Validation/StrictRules/FormatRules.php
+++ b/system/Validation/StrictRules/FormatRules.php
@@ -184,18 +184,10 @@ public function hex($str = null): bool
     /**
      * Integer
      *
-     * @param mixed $str
+     * @param int|null $str
      */
     public function integer($str = null): bool
     {
-        if (is_int($str)) {
-            $str = (string) $str;
-        }
-
-        if (! is_string($str)) {
-            return false;
-        }
-
         return $this->nonStrictFormatRules->integer($str);
     }
 
@@ -238,7 +230,7 @@ public function is_natural_no_zero($str = null): bool
     /**
      * Numeric
      *
-     * @param mixed $str
+     * @param float|int|string|null $str
      */
     public function numeric($str = null): bool
     {
diff --git a/tests/system/CodeIgniterTest.php b/tests/system/CodeIgniterTest.php
index f3f8bf7442f8..7b626032778b 100644
--- a/tests/system/CodeIgniterTest.php
+++ b/tests/system/CodeIgniterTest.php
@@ -655,7 +655,7 @@ public function testPageCacheWithCacheQueryString($cacheQueryStringValue, int $e
             $routes->add($testingUrl, static function () {
                 CodeIgniter::cache(0); // Dont cache the page in the run() function because CodeIgniter class will create default $cacheConfig and overwrite settings from the dataProvider
                 $response = Services::response();
-                $string = 'This is a test page, to check cache configuration';
+                $string   = 'This is a test page, to check cache configuration';
 
                 return $response->setBody($string);
             });
diff --git a/tests/system/Validation/FormatRulesTest.php b/tests/system/Validation/FormatRulesTest.php
index bf9bf92eb6dc..434c4c14ee68 100644
--- a/tests/system/Validation/FormatRulesTest.php
+++ b/tests/system/Validation/FormatRulesTest.php
@@ -809,13 +809,43 @@ public function testIntegerWithInvalidTypeData($value, bool $expected): void
         $data = [
             'foo' => $value,
         ];
-        $this->assertsame($expected, $this->validation->run($data));
+        $this->assertSame($expected, $this->validation->run($data));
+    }
+
+    public function integerInvalidTypeDataProvider(): Generator
+    {
+        // TypeError : CodeIgniter\Validation\FormatRules::integer(): Argument #1 ($str) must be of type ?string, array given
+        // yield 'array with int' => [
+        // [555],
+        // false,
+        // ];
+
+        // TypeError : CodeIgniter\Validation\FormatRules::integer(): Argument #1 ($str) must be of type ?string, array given
+        // yield 'empty array' => [
+        // [],
+        // false,
+        // ];
+
+        yield 'bool true' => [
+            true,
+            false,
+        ];
+
+        yield 'bool false' => [
+            false,
+            false,
+        ];
+
+        yield 'null' => [
+            null,
+            false,
+        ];
     }
 
     /**
      * @see https://github.com/codeigniter4/CodeIgniter4/issues/5374
      *
-     * @dataProvider integerInvalidTypeDataProvider
+     * @dataProvider numericInvalidTypeDataProvider
      *
      * @param mixed $value
      */
@@ -828,18 +858,18 @@ public function testNumericWithInvalidTypeData($value, bool $expected): void
         $data = [
             'foo' => $value,
         ];
-        $this->assertsame($expected, $this->validation->run($data));
+        $this->assertSame($expected, $this->validation->run($data));
     }
 
-    public function integerInvalidTypeDataProvider(): Generator
+    public function numericInvalidTypeDataProvider(): Generator
     {
-        // TypeError : CodeIgniter\Validation\FormatRules::integer(): Argument #1 ($str) must be of type ?string, array given
+        // TypeError : CodeIgniter\Validation\FormatRules::numeric(): Argument #1 ($str) must be of type ?string, array given
         // yield 'array with int' => [
         // [555],
         // false,
         // ];
 
-        // TypeError : CodeIgniter\Validation\FormatRules::integer(): Argument #1 ($str) must be of type ?string, array given
+        // TypeError : CodeIgniter\Validation\FormatRules::numeric(): Argument #1 ($str) must be of type ?string, array given
         // yield 'empty array' => [
         // [],
         // false,
@@ -863,8 +893,10 @@ public function integerInvalidTypeDataProvider(): Generator
 
     /**
      * @dataProvider integerProvider
+     *
+     * @param int|string|null $str
      */
-    public function testInteger(?string $str, bool $expected): void
+    public function testInteger($str, bool $expected): void
     {
         $data = [
             'foo' => $str,
@@ -881,16 +913,24 @@ public function integerProvider(): Generator
     {
         yield from [
             [
-                '0',
+                1,
                 true,
             ],
+            [
+                1.5,
+                false,
+            ],
+            [
+                '0',
+                false,
+            ],
             [
                 '42',
-                true,
+                false,
             ],
             [
                 '-1',
-                true,
+                false,
             ],
             [
                 "+42\n",
diff --git a/tests/system/Validation/StrictRules/FormatRulesTest.php b/tests/system/Validation/StrictRules/FormatRulesTest.php
index c1a060f51664..25893cb8c425 100644
--- a/tests/system/Validation/StrictRules/FormatRulesTest.php
+++ b/tests/system/Validation/StrictRules/FormatRulesTest.php
@@ -813,10 +813,38 @@ public function testIntegerWithInvalidTypeData($value, bool $expected): void
         $this->assertsame($expected, $this->validation->run($data));
     }
 
+    public function integerInvalidTypeDataProvider(): Generator
+    {
+        yield 'array with int' => [
+            [555],
+            false,  // TypeError in Traditional Rule
+        ];
+
+        yield 'empty array' => [
+            [],
+            false,  // TypeError in Traditional Rule
+        ];
+
+        yield 'bool true' => [
+            true,
+            false,  // true in Traditional Rule
+        ];
+
+        yield 'bool false' => [
+            false,
+            false,
+        ];
+
+        yield 'null' => [
+            null,
+            false,
+        ];
+    }
+
     /**
      * @see https://github.com/codeigniter4/CodeIgniter4/issues/5374
      *
-     * @dataProvider integerInvalidTypeDataProvider
+     * @dataProvider numericInvalidTypeDataProvider
      *
      * @param mixed $value
      */
@@ -832,21 +860,11 @@ public function testNumericWithInvalidTypeData($value, bool $expected): void
         $this->assertsame($expected, $this->validation->run($data));
     }
 
-    public function integerInvalidTypeDataProvider(): Generator
+    public function numericInvalidTypeDataProvider(): Generator
     {
-        yield 'array with int' => [
-            [555],
-            false,  // TypeError in Traditional Rule
-        ];
-
-        yield 'empty array' => [
-            [],
-            false,  // TypeError in Traditional Rule
-        ];
-
         yield 'bool true' => [
             true,
-            false,  // true in Traditional Rule
+            false,
         ];
 
         yield 'bool false' => [
@@ -862,8 +880,10 @@ public function integerInvalidTypeDataProvider(): Generator
 
     /**
      * @dataProvider integerProvider
+     *
+     * @param int|string|null $str
      */
-    public function testInteger(?string $str, bool $expected): void
+    public function testInteger($str, bool $expected): void
     {
         $data = [
             'foo' => $str,
@@ -880,16 +900,24 @@ public function integerProvider(): Generator
     {
         yield from [
             [
-                '0',
+                1,
                 true,
             ],
+            [
+                1.5,
+                false,
+            ],
+            [
+                '0',
+                false,
+            ],
             [
                 '42',
-                true,
+                false,
             ],
             [
                 '-1',
-                true,
+                false,
             ],
             [
                 "+42\n",
diff --git a/user_guide_src/source/libraries/validation.rst b/user_guide_src/source/libraries/validation.rst
index 6b50b7331e7f..83871bbe58c5 100644
--- a/user_guide_src/source/libraries/validation.rst
+++ b/user_guide_src/source/libraries/validation.rst
@@ -211,7 +211,6 @@ It works for most basic cases like validating POST data.
 
 However, for example, if you use JSON input data, it may be a type of bool/null/array.
 When you validate the boolean ``true``, it is converted to string ``'1'`` with the Traditional rule classes.
-If you validate it with the ``integer`` rule, ``'1'`` passes the validation.
 
 The **Strict Rules** don't use implicit type conversion.