diff --git a/src/Drivers/Gd/Encoders/WebpEncoder.php b/src/Drivers/Gd/Encoders/WebpEncoder.php
index e7d344a1..076c9155 100644
--- a/src/Drivers/Gd/Encoders/WebpEncoder.php
+++ b/src/Drivers/Gd/Encoders/WebpEncoder.php
@@ -18,7 +18,7 @@ class WebpEncoder extends GenericWebpEncoder implements SpecializedInterface
      */
     public function encode(ImageInterface $image): EncodedImage
     {
-        $quality = $this->quality === 100 ? IMG_WEBP_LOSSLESS : $this->quality;
+        $quality = $this->quality === 100 && defined('IMG_WEBP_LOSSLESS') ? IMG_WEBP_LOSSLESS : $this->quality;
 
         return $this->createEncodedImage(function ($pointer) use ($image, $quality): void {
             imagewebp($image->core()->native(), $pointer, $quality);