Free forever · Nothing uploaded
True lossless compression that doesn't touch a single pixel — or dial the quality down by any percentage you like. Images, PDFs, documents and audio, all compressed inside your own browser.
Compression runs on your own device. The first file of each type downloads its codec (a few hundred KB), then everything after that is instant.
What it shrinks
Plenty of tools call everything "lossless". We only use the word where the file genuinely decodes to identical pixels.
Rebuilt with oxipng — the same engine the professionals use. Identical image, smaller file.
typically 20–60% smallerRe-encoded with MozJPEG, which packs the same picture into far fewer bytes than a camera does.
typically 40–70% smallerModern formats that beat JPG badly. AVIF is the smallest thing on the web right now.
up to 80% smaller than JPGTidied losslessly, or rebuilt from images for scans. We'll warn you before doing anything drastic.
5–15%, or 70–90% on scansMinified with SVGO. Strips editor junk, comments and pointless decimal places.
typically 30–70% smallerOptimised with gifsicle, animation intact. Colour reduction available if you want more.
typically 15–30% smallerOffice files are zip archives. We repack them tighter and drop the preview thumbnails.
typically 5–20% smallerWAV files are enormous. Convert to MP3 at a bitrate you choose and watch them collapse.
typically 90% smallerQuestions
The file gets smaller but decodes to exactly the same pixels — you could compare them pixel by pixel and find no difference. It works because most files are stored inefficiently in the first place. PNG, SVG, GIF and Office files can all be genuinely losslessly compressed.
No, and we won't pretend otherwise. A JPG has to be decoded and re-encoded, so it's technically a fresh generation. At 90% quality it's visually identical to almost anyone and usually much smaller. The genuinely lossless part for a JPG is stripping its hidden metadata, which we do automatically.
Never. Everything runs in your browser on your own device. Nothing is transmitted to us, which is why you can safely compress contracts, invoices and client work.
Text-based PDFs are already efficiently stored, so lossless mode only finds 5–15%. The big savings come from scanned documents, where scan mode can remove 70–90%. It will make text non-selectable, so we warn you first.
AVIF if you want the smallest possible file and only need modern browsers. WebP is the safe middle ground with near-universal support. JPG if it has to work absolutely everywhere. For logos and flat graphics, keep PNG and use lossless mode.
Not yet. Browser-based video compression means a very large download before anything happens and it can crash phones on bigger files. Tell us below if you'd use it.
Made in Pakenham
Squish, Onvert, Undersign and Qwirl are free because we'd rather be useful first. When you need the bigger work done properly, that's the day job.
