diff --git a/src/Type/Types/IntegerRangeType.php b/src/Type/Types/IntegerRangeType.php
index 2c282903..7df97ea1 100644
--- a/src/Type/Types/IntegerRangeType.php
+++ b/src/Type/Types/IntegerRangeType.php
@@ -11,6 +11,9 @@
 use CuyZ\Valinor\Type\Parser\Exception\Scalar\SameValueForIntegerRange;
 use CuyZ\Valinor\Type\Type;
 
+use function is_string;
+use function ltrim;
+use function preg_match;
 use function sprintf;
 
 /** @internal */
@@ -79,6 +82,12 @@ public function matches(Type $other): bool
 
     public function canCast(mixed $value): bool
     {
+        if (is_string($value)) {
+            $value = preg_match('/^0+$/', $value)
+                ? '0'
+                : ltrim($value, '0');
+        }
+
         return ! is_bool($value)
             && filter_var($value, FILTER_VALIDATE_INT) !== false
             && $value >= $this->min
diff --git a/src/Type/Types/IntegerValueType.php b/src/Type/Types/IntegerValueType.php
index f6cd7033..23a22703 100644
--- a/src/Type/Types/IntegerValueType.php
+++ b/src/Type/Types/IntegerValueType.php
@@ -13,6 +13,9 @@
 use function assert;
 use function filter_var;
 use function is_bool;
+use function is_string;
+use function ltrim;
+use function preg_match;
 
 /** @internal */
 final class IntegerValueType implements IntegerType, FixedType
@@ -55,6 +58,12 @@ public function matches(Type $other): bool
 
     public function canCast(mixed $value): bool
     {
+        if (is_string($value)) {
+            $value = preg_match('/^0+$/', $value)
+                ? '0'
+                : ltrim($value, '0');
+        }
+
         return ! is_bool($value)
             && filter_var($value, FILTER_VALIDATE_INT) !== false
             && (int)$value === $this->value; // @phpstan-ignore-line;
diff --git a/src/Type/Types/NativeIntegerType.php b/src/Type/Types/NativeIntegerType.php
index f03f9e57..70249b08 100644
--- a/src/Type/Types/NativeIntegerType.php
+++ b/src/Type/Types/NativeIntegerType.php
@@ -14,6 +14,8 @@
 use function filter_var;
 use function is_bool;
 use function is_int;
+use function is_string;
+use function ltrim;
 
 /** @internal */
 final class NativeIntegerType implements IntegerType
@@ -37,6 +39,10 @@ public function matches(Type $other): bool
 
     public function canCast(mixed $value): bool
     {
+        if (is_string($value)) {
+            $value = ltrim($value, '0') . '0';
+        }
+
         return ! is_bool($value) && filter_var($value, FILTER_VALIDATE_INT) !== false;
     }
 
diff --git a/src/Type/Types/NonNegativeIntegerType.php b/src/Type/Types/NonNegativeIntegerType.php
index ff6c5f04..8a3b87b8 100644
--- a/src/Type/Types/NonNegativeIntegerType.php
+++ b/src/Type/Types/NonNegativeIntegerType.php
@@ -10,6 +10,9 @@
 use CuyZ\Valinor\Type\Type;
 use CuyZ\Valinor\Utility\IsSingleton;
 
+use function is_string;
+use function ltrim;
+
 /** @internal */
 final class NonNegativeIntegerType implements IntegerType
 {
@@ -33,6 +36,10 @@ public function matches(Type $other): bool
 
     public function canCast(mixed $value): bool
     {
+        if (is_string($value)) {
+            $value = ltrim($value, '0') . '0';
+        }
+
         return ! is_bool($value)
             && filter_var($value, FILTER_VALIDATE_INT) !== false
             && $value >= 0;
diff --git a/src/Type/Types/PositiveIntegerType.php b/src/Type/Types/PositiveIntegerType.php
index 1b2e135a..f15882db 100644
--- a/src/Type/Types/PositiveIntegerType.php
+++ b/src/Type/Types/PositiveIntegerType.php
@@ -14,6 +14,8 @@
 use function filter_var;
 use function is_bool;
 use function is_int;
+use function is_string;
+use function ltrim;
 
 /** @internal */
 final class PositiveIntegerType implements IntegerType
@@ -38,6 +40,10 @@ public function matches(Type $other): bool
 
     public function canCast(mixed $value): bool
     {
+        if (is_string($value)) {
+            $value = ltrim($value, '0');
+        }
+
         return ! is_bool($value)
             && filter_var($value, FILTER_VALIDATE_INT) !== false
             && $value > 0;
diff --git a/tests/Integration/Mapping/Other/FlexibleCastingMappingTest.php b/tests/Integration/Mapping/Other/FlexibleCastingMappingTest.php
index ea630bd3..fb09d16a 100644
--- a/tests/Integration/Mapping/Other/FlexibleCastingMappingTest.php
+++ b/tests/Integration/Mapping/Other/FlexibleCastingMappingTest.php
@@ -24,6 +24,71 @@ protected function setUp(): void
         $this->mapper = (new MapperBuilder())->enableFlexibleCasting()->mapper();
     }
 
+    public function test_leading_zero_in_numeric_is_mapped_properly(): void
+    {
+        $source = ['000', '040', '00040', '0001337.404'];
+
+        try {
+            $result = $this->mapper->map('array<int|float>', $source);
+        } catch (MappingError $error) {
+            $this->mappingFail($error);
+        }
+
+        self::assertSame([0, 40, 40, 1337.404], $result);
+    }
+
+    public function test_leading_zero_in_integer_range_is_mapped_properly(): void
+    {
+        $source = ['060', '042', '000404'];
+
+        try {
+            $result = $this->mapper->map('array<int<1, 500>>', $source);
+        } catch (MappingError $error) {
+            $this->mappingFail($error);
+        }
+
+        self::assertSame([60, 42, 404], $result);
+    }
+
+    public function test_leading_zero_in_integer_value_is_mapped_properly(): void
+    {
+        $source = ['000', '040', '000404'];
+
+        try {
+            $result = $this->mapper->map('array<0|40|404>', $source);
+        } catch (MappingError $error) {
+            $this->mappingFail($error);
+        }
+
+        self::assertSame([0, 40, 404], $result);
+    }
+
+    public function test_leading_zero_in_positive_integer_is_mapped_properly(): void
+    {
+        $source = ['040', '000404'];
+
+        try {
+            $result = $this->mapper->map('array<positive-int>', $source);
+        } catch (MappingError $error) {
+            $this->mappingFail($error);
+        }
+
+        self::assertSame([40, 404], $result);
+    }
+
+    public function test_leading_zero_in_non_negative_integer_is_mapped_properly(): void
+    {
+        $source = ['000', '040', '000404'];
+
+        try {
+            $result = $this->mapper->map('array<non-negative-int>', $source);
+        } catch (MappingError $error) {
+            $this->mappingFail($error);
+        }
+
+        self::assertSame([0, 40, 404], $result);
+    }
+
     public function test_array_of_scalars_is_mapped_properly(): void
     {
         $source = ['foo', 42, 1337.404];