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Protect PDF

Lock a PDF so it asks for a password when opened. The file is encrypted on this device and never sent to a server.

Add one PDF to protect.

or drop a file here

Files never leave your device. Everything runs in your browser.

How to use it

  1. Click "Choose a file" or drop the PDF you want to lock.
  2. Enter a password of at least 4 characters and repeat it.
  3. Turn on "Also block printing, editing and copying" if you want those restrictions too.
  4. Click "Protect PDF" and download the locked file.

What it does

  • AES-256 encryption

    Uses AES-256, the strongest encryption in the PDF standard, so the content can't be read without the password.

  • Print, edit and copy limits

    Optionally add permission settings that stop printing, editing and copying text.

  • No typos

    Type the password twice to confirm it, and use "Show" to check what you typed.

  • No upload

    Neither the PDF nor the password leaves your device; encryption happens in your browser.

Good to know

Payslips, contracts and ID scans shouldn't travel by email or chat without protection. An open password keeps them unreadable to anyone who intercepts or forwards the file. Share the password a different way, for example by text message.

This site doesn't store your password, so a forgotten password can't be recovered. The print, edit and copy limits are standard PDF permissions that most viewers respect, though some programs ignore them, so treat the open password as the real protection. To remove the password later, use Unlock PDF.

Questions and answers

Is it free to password protect a PDF?

Yes. There's no sign-up, and your file and password stay on your device.

What if I forget the password?

It can't be recovered, and this site doesn't store it, so keep it somewhere safe.

Which encryption is used?

AES-256 as defined in PDF 2.0. Most PDF viewers open the file as soon as you type the password.

Can I protect a PDF that already has a password?

Remove the old password first with Unlock PDF, then add the new one.

Can I block only printing?

For now the option blocks printing, editing and copying together. Without it, only the open password is set.

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