画像圧縮ツール
画像をオンラインで圧縮し、品質を失わずにファイルサイズを縮小。JPEG、PNG、WebPをサポート。品質を調整、結果をプレビュー、即座にダウンロード。100%純クライアントサイド — サーバーへのアップロードなし。
About Image Compressor
Compress images to reduce file size for faster web loading, email attachments, and storage optimization. This tool uses the HTML5 Canvas API to compress images entirely in your browser — your images never leave your device. Adjust quality to find the perfect balance between file size and visual fidelity.
Features
- 100% client-side processing — images never uploaded to any server
- Adjustable compression quality with real-time preview
- Support for JPEG, PNG, and WebP output formats
- Compare original and compressed file sizes instantly
- Drag & drop or click to upload — no installation needed
- Download compressed images in one click
Common Use Cases
- Optimize images for faster website loading
- Reduce email attachment sizes
- Compress photos for social media uploads
- Shrink images for storage optimization
FAQ
Is my image data safe?
Yes. All compression happens directly in your browser using the Canvas API. Your images are never transmitted to any server.
What formats are supported?
Input: PNG, JPEG, WebP. Output: JPEG (best compression), PNG (lossless), WebP (modern efficient).
Does compression reduce image dimensions?
No. This tool only reduces file size through compression. Use our Image Resizer if you need to change dimensions.
What is the maximum file size?
Maximum upload size is 10MB, which covers most common use cases.