How the image compressor works
The compressor redraws your image onto an HTML canvas and re-encodes it at the quality level you choose. Lower quality settings discard more visual detail in exchange for a smaller file — JPEG and WebP both support this trade-off; PNG (lossless) does not, which is why it isn't offered as an output format here.
Step-by-step guide
- Choose an image file from your device.
- Select JPEG or WebP as the output format.
- Adjust the quality slider and watch the compressed size update live.
- Download the compressed image once you're happy with the size/quality trade-off.
Why compress images at all
Smaller image files load faster, which directly improves page speed metrics like Largest Contentful Paint — a meaningful factor in both user experience and search ranking. Compressing images before uploading them to a website is one of the highest-leverage, easiest performance improvements available.
Frequently asked questions
No — compression happens entirely in your browser using the Canvas API. The image never leaves your device.
PNG is a lossless format with no quality slider to adjust — compressing a PNG meaningfully requires reducing its color palette, a different technique than the quality-based compression used here. Convert to JPEG or WebP instead for adjustable lossy compression, or use our Image Format Converter.
70–80% is a common sweet spot that meaningfully reduces file size with minimal visible quality loss for most photos. Go lower for thumbnails or where file size matters more than fine detail.
WebP generally achieves a smaller file size than JPEG at a similar visual quality, but isn't supported by every older tool or platform — check your use case's compatibility requirements.