Compress PDF

Almost every PDF compressor online works by uploading your document to a server, shrinking it there, and sending it back. That means your contract, tax return, passport scan or medical record sits on someone else's machine — however briefly. pdfcdf compresses entirely inside your browser, so the file never leaves your device. There's nothing to delete afterwards and no retention policy to read.

It's also free with no limits: no daily cap on how many files you can compress, no watermark on the result, no account, and no upsell to a paid plan once you've tried it twice.

Use Light when the document's text matters — a contract you'll search later, a report someone needs to copy from, anything going through automated processing. It rewrites the file structure losslessly, so quality is untouched and text stays selectable, though savings are smaller.

Use Balanced for the everyday problem of a file that's a few megabytes over an email or upload limit. Use Strong for scanned paperwork where you just need it readable and small — phone-camera scans in particular are enormous by default and shrink dramatically at this level.