diff --git a/phpstan-baseline.neon b/phpstan-baseline.neon
index 65679108..3156b310 100644
--- a/phpstan-baseline.neon
+++ b/phpstan-baseline.neon
@@ -12,7 +12,7 @@ parameters:
 
 		-
 			message: "#^Parameter \\#1 \\$data of function imagecreatefromstring expects string, string\\|false given\\.$#"
-			count: 2
+			count: 1
 			path: src/Drivers/Gd/GdDriver.php
 
 		-
@@ -102,7 +102,7 @@ parameters:
 
 		-
 			message: "#^Property Spatie\\\\Image\\\\Drivers\\\\Gd\\\\GdDriver\\:\\:\\$image \\(GdImage\\) does not accept GdImage\\|false\\.$#"
-			count: 3
+			count: 2
 			path: src/Drivers/Gd/GdDriver.php
 
 		-
diff --git a/src/Drivers/Gd/GdDriver.php b/src/Drivers/Gd/GdDriver.php
index 66d3d66f..06f4d946 100644
--- a/src/Drivers/Gd/GdDriver.php
+++ b/src/Drivers/Gd/GdDriver.php
@@ -35,6 +35,8 @@ class GdDriver implements ImageDriver
 
     protected GdImage $image;
 
+    protected ?string $format = null;
+
     /** @var array<string, mixed> */
     protected array $exif = [];
 
@@ -131,9 +133,11 @@ public function save(?string $path = null): static
         if (! $path) {
             $path = $this->originalPath;
         }
-
-        $extension = pathinfo($path, PATHINFO_EXTENSION);
-
+        if (is_null($this->format)) {
+            $extension = pathinfo($path, PATHINFO_EXTENSION);
+        } else {
+            $extension = $this->format;
+        }
         switch (strtolower($extension)) {
             case 'jpg':
             case 'jpeg':
@@ -158,6 +162,7 @@ public function save(?string $path = null): static
         if ($this->optimize) {
             $this->optimizerChain->optimize($path);
         }
+        $this->format = null;
 
         return $this;
     }
@@ -166,7 +171,26 @@ public function base64(string $imageFormat = 'jpeg', bool $prefixWithFormat = tr
     {
         ob_start();
 
-        $this->format($imageFormat);
+        switch (strtolower($imageFormat)) {
+            case 'jpg':
+            case 'jpeg':
+                imagejpeg($this->image, null, $this->quality);
+                break;
+            case 'png':
+                imagepng($this->image, null, $this->pngCompression());
+                break;
+            case 'gif':
+                imagegif($this->image, null);
+                break;
+            case 'webp':
+                imagewebp($this->image, null);
+                break;
+            case 'avif':
+                imageavif($this->image, null);
+                break;
+            default:
+                throw UnsupportedImageFormat::make($imageFormat);
+        }
 
         $imageData = ob_get_contents();
         ob_end_clean();
@@ -687,32 +711,10 @@ protected function pngCompression(): int
 
     public function format(string $format): static
     {
-        ob_start();
-
-        switch (strtolower($format)) {
-            case 'jpg':
-            case 'jpeg':
-                imagejpeg($this->image, null, $this->quality);
-                break;
-            case 'png':
-                imagepng($this->image, null, $this->pngCompression());
-                break;
-            case 'gif':
-                imagegif($this->image, null);
-                break;
-            case 'webp':
-                imagewebp($this->image, null);
-                break;
-            case 'avif':
-                imageavif($this->image, null);
-                break;
-            default:
-                throw UnsupportedImageFormat::make($format);
+        if (! in_array($format, ['jpg', 'jpeg', 'png', 'gif', 'webp', 'avif'])) {
+            throw UnsupportedImageFormat::make($format);
         }
-
-        $this->image = imagecreatefromstring(ob_get_contents());
-
-        ob_end_clean();
+        $this->format = $format;
 
         return $this;
     }
diff --git a/tests/ImageFormatTest.php b/tests/ImageFormatTest.php
index 86527360..a4446a56 100644
--- a/tests/ImageFormatTest.php
+++ b/tests/ImageFormatTest.php
@@ -25,7 +25,7 @@
 
         return;
     }
-    $driver->loadFile(getTestJpg())->format($format);
+    $driver->loadFile(getTestJpg())->format($format)->save($this->tempDir->path("{$driver->driverName()}/format-test.$format"));
 })->with('drivers', ['jpeg', 'gif', 'png', 'webp', 'avif'])->throwsNoExceptions();
 
 it('can save tiff', function () {