Protect PDF
Encrypt a PDF with AES-256 — set the new password in the options below.
or drop files here to compress
Max file size 1 GB. Browser-side conversions have no upload limit.
How it works
Add your files
Drop PDF files above or click Choose Files.
Protect
Tweak the settings via the gear icon, then click Protect.
Download
Grab the result — done.
Frequently asked questions
Drop your files into the box above (or click Choose Files), adjust the options via the gear icon if you like, then click Protect and download the result.
Yes — completely free, with no watermarks and no sign-up.
Conversions that can run in your browser never upload your file at all (look for the "In your browser" badge). Everything else is sent over an encrypted connection and automatically deleted within an hour.
It depends on the source. Use the gear icon to trade quality for size — stronger settings give smaller files.