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How to Password-Protect (and Unlock) a PDF

June 26, 2026 1 min read

Some documents shouldn't be readable by just anyone. Bank statements, contracts, medical records — these deserve a password. Here's how to add one, and how to remove it when you no longer need it.

Add a password (encrypt)

Protect PDF encrypts your file with AES, the same class of encryption used to secure websites. Anyone who opens the file must enter the password.

  1. Open Protect PDF.
  2. Choose a strong password and confirm it.
  3. Download the encrypted PDF.

Because the encryption happens in your browser, your file and your password are never uploaded — there's no server that could leak them.

Keep your password somewhere safe. There's no backdoor: if you lose it, the file can't be opened.

Restrict what people can do

Sometimes you want people to read a document but not print or copy it. PDF Permissions lets you set an owner password and toggle exactly that — printing, copying, editing, form-filling and more — without requiring a password just to open the file.

Remove a password you know

Tired of typing the password every time you open a file you own? Unlock PDF removes the encryption — you just need the current password. This is for documents you're authorised to open; it doesn't crack unknown passwords.

Verify a file hasn't been tampered with

For an extra layer of trust, generate a PDF fingerprint (a SHA-256 checksum). Anyone can later verify that the file is byte-for-byte identical to the original.

Tools used in this guide

password protect pdfencrypt pdfunlock pdfremove pdf passwordpdf permissions