diff --git a/src/Domain/Scraping/Infrastructure/Service/ImageDownloader.php b/src/Domain/Scraping/Infrastructure/Service/ImageDownloader.php
index eafd788..a886bcc 100644
--- a/src/Domain/Scraping/Infrastructure/Service/ImageDownloader.php
+++ b/src/Domain/Scraping/Infrastructure/Service/ImageDownloader.php
@@ -21,12 +21,34 @@ readonly class ImageDownloader implements ImageDownloaderInterface
     public function download(string $url, string $destination): void
     {
         $response = $this->httpClient->request('GET', $url);
+        $contentType = $response->getHeaders()['content-type'][0] ?? '';
 
-        if (!str_starts_with($response->getHeaders()['content-type'][0], 'image/')) {
-            throw new \RuntimeException('Invalid content type');
+        if (!str_starts_with($contentType, 'image/')) {
+            throw new \RuntimeException('Invalid content type: ' . $contentType);
         }
 
-        file_put_contents($destination, $response->getContent());
+        $imageData = $response->getContent();
+        $tempFilePath = $this->saveTempFile($imageData);
+
+        try {
+            $image = $this->createImageResource($tempFilePath, $contentType);
+            if (false === $image) {
+                throw new \RuntimeException('Failed to create image resource');
+            }
+
+            $destination = $this->ensureJpgExtension($destination);
+            if (!imagejpeg($image, $destination)) {
+                imagedestroy($image);
+                unlink($tempFilePath);
+                throw new \RuntimeException('Failed to save image as JPG');
+            }
+
+            imagedestroy($image);
+        } finally {
+            if (file_exists($tempFilePath)) {
+                unlink($tempFilePath);
+            }
+        }
     }
 
     public function downloadBatch(array $urls, TempDirectory $tempDir, string $jobId): array
@@ -36,12 +58,10 @@ readonly class ImageDownloader implements ImageDownloaderInterface
 
         foreach ($urls as $index => $url) {
             try {
-                $extension = pathinfo(parse_url($url, PHP_URL_PATH), PATHINFO_EXTENSION) ?: 'jpg';
                 $destination = sprintf(
-                    '%s/%03d.%s',
+                    '%s/%03d.jpg',
                     $tempDir->getPath(),
-                    $index + 1,
-                    $extension
+                    $index + 1
                 );
 
                 $this->download($url, $destination);
@@ -68,4 +88,74 @@ readonly class ImageDownloader implements ImageDownloaderInterface
             new ScrapingProgress($currentPage, $totalPages)
         ));
     }
+
+    private function saveTempFile(string $data): string
+    {
+        $tempFilePath = tempnam(sys_get_temp_dir(), 'manga_img_');
+        file_put_contents($tempFilePath, $data);
+
+        return $tempFilePath;
+    }
+
+    /**
+     * @throws \RuntimeException
+     */
+    private function createImageResource(string $filePath, string $contentType)
+    {
+        $realFormat = $this->detectImageFormat($filePath);
+
+        return match ($realFormat) {
+            'webp' => imagecreatefromwebp($filePath),
+            'png' => imagecreatefrompng($filePath),
+            'jpeg' => imagecreatefromjpeg($filePath),
+            'gif' => imagecreatefromgif($filePath),
+            'bmp' => imagecreatefromwbmp($filePath),
+            default => throw new \RuntimeException('Unsupported image format: ' . $realFormat . ' (content-type: ' . $contentType . ')'),
+        };
+    }
+
+    private function detectImageFormat(string $filePath): string
+    {
+        $handle = fopen($filePath, 'rb');
+        if (!$handle) {
+            throw new \RuntimeException('Cannot open file for format detection');
+        }
+
+        $header = fread($handle, 12);
+        fclose($handle);
+
+        // JPEG: starts with FF D8 FF
+        if (str_starts_with($header, "\xFF\xD8\xFF")) {
+            return 'jpeg';
+        }
+
+        // PNG: starts with 89 50 4E 47 0D 0A 1A 0A
+        if (str_starts_with($header, "\x89PNG\r\n\x1A\n")) {
+            return 'png';
+        }
+
+        // WebP: starts with RIFF....WEBP
+        if (str_starts_with($header, 'RIFF') && strpos($header, 'WEBP', 8) === 8) {
+            return 'webp';
+        }
+
+        // GIF: starts with GIF87a or GIF89a
+        if (str_starts_with($header, 'GIF87a') || str_starts_with($header, 'GIF89a')) {
+            return 'gif';
+        }
+
+        // BMP: starts with BM
+        if (str_starts_with($header, 'BM')) {
+            return 'bmp';
+        }
+
+        throw new \RuntimeException('Unknown image format. Header: ' . bin2hex(substr($header, 0, 8)));
+    }
+
+    private function ensureJpgExtension(string $path): string
+    {
+        $info = pathinfo($path);
+
+        return $info['dirname'] . '/' . $info['filename'] . '.jpg';
+    }
 }