画像圧縮

ブラウザでJPGとPNG画像を圧縮。品質を維持しながらファイルサイズを60-80%削減。100%プライバシー保護、アップロード不要。

ここに画像をドラッグ＆ドロップ、またはクリックして選択

貼り付けもできます (Ctrl+V)

機能

100% ブラウザ完結

すべての圧縮はブラウザ上で行われます。画像が端末を離れることはありません。

一括圧縮

複数の画像を一度に圧縮。一度に最大50画像を処理可能。

品質管理

「サイズ最適化」または「品質保持」から選択、またはスライダーでカスタマイズ。

即時プレビュー

圧縮結果を即座に確認、圧縮前後のファイルサイズ比較。

How to Compress Images?

Drag and drop images onto the upload area, or click to select files.
Choose compression mode: "Optimize Size", "Keep Quality", or "Custom".
Adjust quality slider if using Custom mode.
Click "Compress All" to process all images, or compress individually.
Download compressed images individually or as a ZIP file.

Common Use Cases

Website Optimization

Compress images to make your website load faster and improve SEO.

Email Attachments

Reduce image size to send via email without hitting attachment limits.

Social Media

Compress images before uploading to social media platforms with file size limits.

Storage Saving

Free up storage space by compressing images stored on your device.

Compression Tips

✓ Use "Optimize Size" mode for maximum compression (60-80% reduction).
✓ Use "Keep Quality" mode when you need near-original quality (20-30% reduction).
✓ PNG with transparent backgrounds may not compress as much as JPG.
✓ Batch process multiple images at once to save time.

よくある質問

Is my image data sent to any server?

No, your images are never sent to any server. All compression happens entirely in your browser using the Canvas API, which means your images stay on your device at all times. This is 100% private and secure.

How much can I compress an image?

It depends on the original image. Typically, you can reduce JPG files by 60-80% and PNG files by 30-50% without visible quality loss. The actual compression ratio depends on the image content and complexity.

What formats are supported?

Currently, we support JPG and PNG compression. Both input and output use the same format by default, but you can convert to different formats using our Image Convert tool.

Is there a file size limit?

We recommend keeping files under 25MB for optimal performance. Files larger than 25MB may cause memory issues on some devices. The tool will warn you if a file is too large.