About Compress Image
Compress Image — free, private, browser-based image tool
Make JPG, PNG, WebP or AVIF images smaller and watch the size and quality change as you move the slider.
Why use Compress Image
- ·Files stay on your device — nothing is uploaded
- ·No signup needed
- ·Works in any modern browser, on any OS
- ·Free daily use; Pro removes limits and watermarks
How to use it
- 1Drop a JPG, PNG, WebP or AVIF image.
- 2Pick the output format — WebP is the default — and move the quality slider (75 default) while watching the size and preview.
- 3Download the smaller image.
Format matters more than the slider
Saving as WebP (the default) or AVIF usually makes a photo far smaller than JPG at the same visible quality. Quality runs from 20 to 100 (default 75); for WebP and AVIF an effort setting trades encoding time for a smaller file. PNG output is lossless, so the quality setting does not apply to it.
Engine
Encoding uses the jsquash builds of MozJPEG, libwebp and libavif — the same codecs behind Google’s Squoosh — compiled to run in your browser.
How it works
Uses Canvas2D and WebGL2 with OffscreenCanvas for parallel processing. Filters run as GPU shaders where supported, falling back to CPU SIMD via WebAssembly. The processing code runs inside the page, so your file is not uploaded to a server — you can confirm this in your browser's DevTools → Network tab.