Protect PDF
Encrypt a PDF with an AES-256 open password and choose viewer permissions. Processing stays in your browser.
PDF files up to 100 MiB. Files and passwords stay in this browser; neither is saved by this tool.
The open password encrypts the document with AES-256. Keep a safe copy of your password; this tool cannot recover it.
Length hint: short password. Consider at least 20 characters in a unique passphrase.
Use a different permissions password to manage restrictions. If blank, a random password is generated and discarded: it cannot be recovered. Your open password still unlocks the document with Unlock PDF.
Use a long, unique passphrase. Passwords are limited to 127 UTF-8 bytes, including after Unicode normalization. Spaces and quotes are preserved; PDF readers may normalize Unicode characters.
Permission flags depend on cooperating PDF viewers. They cannot guarantee that someone who can open the PDF will not copy or change it.
AES-256 readers generally permit accessibility extraction regardless of this flag. Turning it off cannot reliably block screen readers.