Password protect a PDF

Add AES-256 encryption to a PDF right in your browser — nothing is uploaded. The protected file opens in any reader with your password.

Drop a PDF here, or click to choose

Nothing is uploaded — it stays in your browser

Encryption runs entirely in your browser with qpdf compiled to WebAssembly. Your file and password never reach our servers — turn off your network and it still works. The output uses standards-compliant AES-256, so it opens in Acrobat, Preview, Chrome, or any PDF reader.

Need to send this PDF to someone, or collect files from clients? ShieldFive does end-to-end encrypted sharing and intake — nothing readable ever touches our servers.

Send it encryptedCollect files from clients

Questions

Is my PDF uploaded anywhere?
No. The encryption runs entirely in your browser with qpdf compiled to WebAssembly. Your file and password never leave your device and are never sent to ShieldFive — you can turn off your network and it still works.
Will the protected PDF open in normal PDF readers?
Yes. It uses standards-compliant PDF AES-256 encryption, so it opens in Adobe Acrobat, Apple Preview, Chrome, and any other PDF reader once you enter the password. This is real PDF encryption, not a proprietary container.
How strong is the encryption?
It uses 256-bit AES, the strongest encryption defined by the PDF standard. The strength of the protection still depends on your password, so choose a long, unique one.
Can I remove a password too?
Yes. Switch to “Remove password”, enter the current password, and you get an unprotected copy — again, entirely in your browser. You can only remove a password you know.
What if I forget the password?
It cannot be recovered. Because nothing is uploaded and no key is stored anywhere, a protected PDF whose password is lost cannot be opened by anyone, including us.