Image compressor
Make a photo smaller without uploading it anywhere.
Or choose a file. It is processed in this tab and never uploaded — which is also why it handles photos far larger than any upload limit.
Choose a fileRe-encodes an image at a lower quality setting so it weighs less. Everything happens in this tab — the file is decoded, drawn to a canvas and encoded again by your own browser — so nothing is uploaded, nothing is stored, and there is no upload limit to work around. A photograph typically loses half its bytes at quality 80 with no difference you can see at normal viewing size.
How it works
- The image is decoded and re-encoded by your browser; the file never leaves the tab.
- Quality is the JPEG or WebP encoder's own setting: lower means smaller and softer, and 80 is where most photographs stop looking different.
- Converting to WebP usually saves another quarter on top of the quality setting.
Where your data goes
Nowhere. This tool runs entirely in your browser: the text you paste is processed by the page and is never transmitted to a server or written to a log.
When a run costs points, a one-line summary is saved to your own history so you can find it again. The summary records the shape of the run — sizes, counts, the values you looked up — never the content you pasted.
What it costs
Free up to 2.00 MB per run without an account. Past that, a run costs 2 points and is saved to your history.
Points come from signing up, checking in daily, commenting and completing your profile.
See how points workCommon questions
- Why did my PNG get bigger?
- PNG is lossless, so the quality setting does nothing for it and re-encoding can easily produce a larger file than the original optimiser did. For a photograph, convert to JPEG or WebP. PNG is the right format for screenshots, diagrams and anything with flat colour or transparency.
- Does compressing lose quality permanently?
- Yes, for JPEG and WebP — they are lossy, and the discarded detail is gone. Keep the original. Re-compressing an already-compressed image repeatedly is what produces the smeared look, because each pass throws away detail the last pass already damaged.
- What quality should I use?
- 80 for photographs on the web. Below 60 the artefacts become visible in flat areas like sky. Above 90 the file grows fast for a difference almost nobody can see.
The open-source behind it
This tool is a self-contained implementation. fengyuanchen/compressorjs (MIT) does the same job as a library — if you need this behaviour inside your own program, start there rather than calling a web page.
fengyuanchen/compressorjsAlso known as
- compress image
- image compressor online
- reduce image size
- compress jpeg
- shrink photo