diff --git a/src/contracts/Repository/Values/Content/Query/Criterion/Image/AbstractImageRangeCriterion.php b/src/contracts/Repository/Values/Content/Query/Criterion/Image/AbstractImageRangeCriterion.php
index 7540c6a3d5..3a3fc4c331 100644
--- a/src/contracts/Repository/Values/Content/Query/Criterion/Image/AbstractImageRangeCriterion.php
+++ b/src/contracts/Repository/Values/Content/Query/Criterion/Image/AbstractImageRangeCriterion.php
@@ -16,26 +16,25 @@
 abstract class AbstractImageRangeCriterion extends Criterion
 {
     /**
-     * @param numeric $minValue
+     * @param numeric|null $minValue
      * @param numeric|null $maxValue
      *
      * @throws \Ibexa\Contracts\Core\Repository\Exceptions\InvalidArgumentException
      */
     public function __construct(
         string $fieldDefIdentifier,
-        $minValue = 0,
+        $minValue = null,
         $maxValue = null
     ) {
         $this->validate($minValue, $maxValue);
-
-        $value[] = $minValue;
-        $operator = Operator::GTE;
+        $value[] = $minValue ?? 0;
 
         if ($maxValue > 0) {
-            $operator = Operator::BETWEEN;
             $value[] = $maxValue;
         }
 
+        $operator = $this->getOperator($value);
+
         parent::__construct(
             $fieldDefIdentifier,
             $operator,
@@ -60,13 +59,23 @@ public function getSpecifications(): array
     }
 
     /**
-     * @param numeric $minValue
+     * @param numeric|null $minValue
      * @param numeric|null $maxValue
      *
      * @throws \Ibexa\Contracts\Core\Repository\Exceptions\InvalidArgumentException
      */
     protected function validate($minValue, $maxValue): void
     {
+        if (
+            null === $minValue
+            && null === $maxValue
+        ) {
+            throw new InvalidArgumentException(
+                implode(', ', ['$minValue', '$maxValue']),
+                'At least one value must be specified.'
+            );
+        }
+
         if ($minValue < 0) {
             throw new InvalidArgumentException(
                 '$minValue',
@@ -76,7 +85,7 @@ protected function validate($minValue, $maxValue): void
 
         if (
             null !== $maxValue
-            && $maxValue <= 0
+            && $maxValue < 0
         ) {
             throw new InvalidArgumentException(
                 '$maxValue',
@@ -94,4 +103,16 @@ protected function validate($minValue, $maxValue): void
             );
         }
     }
+
+    /**
+     * @param array{0: numeric, 1?: numeric|null} $value
+     */
+    private function getOperator(array $value): string
+    {
+        if (count($value) === 2) {
+            return Operator::BETWEEN;
+        }
+
+        return Operator::GTE;
+    }
 }
diff --git a/src/contracts/Repository/Values/Content/Query/Criterion/Image/FileSize.php b/src/contracts/Repository/Values/Content/Query/Criterion/Image/FileSize.php
index 9ca824e6e4..e14044df4e 100644
--- a/src/contracts/Repository/Values/Content/Query/Criterion/Image/FileSize.php
+++ b/src/contracts/Repository/Values/Content/Query/Criterion/Image/FileSize.php
@@ -12,16 +12,11 @@ final class FileSize extends AbstractImageRangeCriterion
 {
     public function __construct(
         string $fieldDefIdentifier,
-        $minValue = 0,
+        $minValue = null,
         $maxValue = null
     ) {
-        if ($minValue > 0) {
-            $minValue *= 1024 * 1024;
-        }
-
-        if ($maxValue > 0) {
-            $maxValue *= 1024 * 1024;
-        }
+        $minValue = $this->convertToBytes($minValue);
+        $maxValue = $this->convertToBytes($maxValue);
 
         parent::__construct(
             $fieldDefIdentifier,
@@ -29,4 +24,21 @@ public function __construct(
             $maxValue
         );
     }
+
+    /**
+     * @param numeric|null $value
+     */
+    private function convertToBytes($value): ?int
+    {
+        if (
+            null === $value
+            || 0 === $value
+        ) {
+            return null;
+        }
+
+        $value *= 1024 * 1024;
+
+        return (int)$value;
+    }
 }
diff --git a/tests/integration/Core/Repository/SearchServiceImageTest.php b/tests/integration/Core/Repository/SearchServiceImageTest.php
index 0d6c0f6731..8c8de7c906 100644
--- a/tests/integration/Core/Repository/SearchServiceImageTest.php
+++ b/tests/integration/Core/Repository/SearchServiceImageTest.php
@@ -84,14 +84,39 @@ public function provideDataForTestCriterion(): iterable
             ),
         ];
 
-        yield 'FileSize - default values min 0 and max 1' => [
+        yield 'FileSize - with numeric values from 0 to 1' => [
             3,
-            $this->createFileSizeCriterion(),
+            $this->createFileSizeCriterion(0, 1),
         ];
 
-        yield 'FileSize' => [
+        yield 'FileSize - with numeric string values from 0.0 to 2.5' => [
             3,
-            $this->createFileSizeCriterion(0, 2),
+            $this->createFileSizeCriterion('0.0', '2.5'),
+        ];
+
+        yield 'FileSize - with numeric values from 0.0 to 2.5' => [
+            3,
+            $this->createFileSizeCriterion(0.0, 2.5),
+        ];
+
+        yield 'FileSize - with numeric values 0.0001 to 0.004' => [
+            2,
+            $this->createFileSizeCriterion(0.001, 0.004),
+        ];
+
+        yield 'FileSize - with values numeric string 0.0003 and numeric 0.3' => [
+            1,
+            $this->createFileSizeCriterion('0.003', 0.3),
+        ];
+
+        yield 'FileSize - min value' => [
+            2,
+            $this->createFileSizeCriterion('0.0002'),
+        ];
+
+        yield 'FileSize - max value' => [
+            1,
+            $this->createFileSizeCriterion(null, '0.0003'),
         ];
 
         yield 'Width' => [
@@ -238,9 +263,13 @@ private function createMimeTypeCriterion($value): Query\Criterion\Image\MimeType
         );
     }
 
+    /**
+     * @param numeric|null $min
+     * @param numeric|null $max
+     */
     private function createFileSizeCriterion(
-        int $min = 0,
-        ?int $max = null
+        $min = 0,
+        $max = null
     ): Query\Criterion\Image\FileSize {
         return new Query\Criterion\Image\FileSize(
             self::IMAGE_FIELD_DEF_IDENTIFIER,