Compress images
Drop in a mixed folder and every file comes back smaller in the format it started as — JPEGs stay JPEGs, PNGs stay PNGs. Each format gets the encoder best suited to it: MozJPEG for JPEG, colour quantisation plus OxiPNG for PNG, and libwebp for WebP. Nothing is uploaded; the compression runs on your own machine.
What to know
- Mixed batches are handled per-file, so you do not need to sort them first.
- If you are willing to change format, converting to WebP or AVIF saves considerably more than recompressing ever will.
- There is no file size limit and no cap on how many images you process, because there is no server paying for it.
Frequently asked questions
- Is there a file size limit?
- No. Everything runs in your browser, so the only limit is your own machine's memory. There is no upload, no queue and no per-file cap.
- Are my images uploaded anywhere?
- No. The compression runs entirely in your browser using WebAssembly. Your files never leave your device. You can verify this in your browser's network tab, or by going offline after the page loads and compressing anyway.
- How many images can I compress at once?
- As many as your machine can hold. Files are processed in parallel across your CPU cores and can be downloaded individually or as a single ZIP.