画像圧縮ツール
画像をドロップし、フォーマットと品質を選択して、圧縮結果をダウンロード。すべてブラウザ内で動作——ファイルはデバイスから外に出ません。
About the image compressor
An image compressor makes a photo smaller in file size while keeping it usable on screen. Drop a JPEG, PNG, or WebP, choose a quality level, and get a lighter file you can email, attach, or upload without hitting a size cap — most camera photos shrink by 60–90% with no visible difference.
Compression runs in your browser using the same canvas engine that draws this page, so the image is never uploaded to a server. Switch the output to WebP for the smallest file, JPEG for the widest compatibility, or PNG when you need the pixels back untouched.
How to compress an image
- 1
Drop an image
Pick or drag a JPEG, PNG, or WebP. It loads straight into the page — there's no upload step.
- 2
Choose format and quality
JPEG, PNG, or WebP, from Best down to Aggressive. The preview and the new file size update with every change.
- 3
Download the smaller file
Save the result and see exactly how much smaller it is than the original.
What the compressor does
Quality you control
Five levels from Best to Aggressive, previewed before you commit to one.
JPEG, PNG, and WebP
Convert while you compress — WebP for the smallest file, JPEG for the widest support.
See the saving
The new size is shown against the original, so you know what you gained.
Never uploaded
Your own browser does the compressing. The image never leaves your device.
Works on any device
No install and no plugin — the same tool on phone, tablet, and desktop.
Free, no signup
No account, no watermark, no daily cap.
Related tools
More free utilities. No signup, and nothing you drop in is uploaded.
FAQ
Compressing images, answered.
What you lose, what you save, and where your photo actually goes.
JPEG and WebP are lossy, so some detail is re-encoded — but at the Best or High setting the difference is usually invisible while the file is far smaller. PNG is lossless: it shrinks without touching a pixel.
No. Compression runs entirely in your browser using the canvas API. The file never leaves your device and nothing is stored.
WebP for the smallest file when you control where it's shown. JPEG when it needs to open anywhere. PNG when you need lossless quality or transparency.
It depends on the photo, but 60–90% smaller is typical for a camera JPEG at the Balanced setting. Fine textures compress less than flat backgrounds.
There's no cap and no queue — but a very large image takes longer, because the work happens on your own device rather than a server.
送りたいものがありますか？
無料で送ろう。
無料プランでは1ファイルあたり10 GBまで。リンクは数秒で発行されます。