Protect PDF with a Password
Encrypt a PDF so it can only be opened with your password, and optionally restrict printing, copying or editing. The encryption runs on your device — the file and password never leave it.
Runs in your browser — nothing is uploaded Free, no limits
PDF file
How to use the PDF Protect
- Choose or drop the PDF you want to protect.
- Type a strong password and repeat it.
- Optionally open “Permissions & advanced options” to block printing, copying or editing.
- Click “Protect & download PDF” — the tool checks the result really requires the password before saving it.
Frequently asked questions
How secure is the protection?
Files are encrypted with AES-256, the strongest standard PDF encryption, supported by Acrobat Reader 9 and later and every modern browser and viewer. The real security depends on your password: a long, random password can’t practically be guessed, a short common one can.
What’s the difference between the open password and the owner password?
The open (user) password is needed to view the file. The owner password controls permissions such as printing and copying. If you leave the owner password empty, a random 32-character one is generated so nobody can lift your restrictions.
Are print and copy restrictions reliable?
They’re honoured by mainstream readers, but they’re not encryption-strength security: some tools ignore them once the file is open. Rely on the open password to keep a file private.
What if I forget the password?
It can’t be recovered — not by us or by this tool. Store it in a password manager. Keep an unprotected copy somewhere safe if losing access would be a problem.
Is my PDF or password uploaded?
No. The PDF is encrypted locally in your browser with the open-source pdf-lib library. Neither the file nor the password is sent anywhere.