Compress a JPG
Shrink JPG file size by adjusting quality. Runs entirely on your device.
What to know
Compression works by re-encoding the image at a lower quality setting. JPG discards fine detail the eye is least sensitive to, so moderate compression is close to invisible while heavy compression produces blocky artefacts around sharp edges and text.
Around 80% is the usual sweet spot for photographs. Screenshots and images containing text suffer noticeably sooner, because JPG handles hard edges badly — for those, PNG or WebP is a better destination.
Questions
Is anything uploaded to a server?
No. Every tool on this site runs inside your browser using standard web APIs. There is no upload, no account, no logging and no server holding your data afterwards. You can confirm it by opening your browser's developer tools and watching the network tab stay empty while you work.
Why did my file get bigger?
Re-encoding at a quality higher than the original cannot recover lost detail, but it can add data. If the source was already heavily compressed, lower the quality setting or leave the file as it is.