MythosPDF
Sign and secure · free PDF tool

Protect a PDF with a password

Set a password that anyone must enter to open the file. The PDF is encrypted with AES 256, the strongest standard PDF encryption, and you choose whether people who open it can print, copy or edit.

Choose a PDF
or drop it here
Free · no sign up · no watermark · up to 100 MB

How to use Protect PDF

  1. 1

    Add your PDF

    Drop in the file you want to lock.

  2. 2

    Set a password

    Type a strong password and choose the permissions.

  3. 3

    Download

    Press Protect PDF. Keep the password somewhere safe; nobody can recover it for you.

Pick a strong password

Encryption is only as strong as the password. Use at least 12 characters mixing words, numbers and symbols, and share it through a different channel than the file.

About permissions

Print, copy and edit permissions are honoured by standard PDF readers, but they are rules for well behaved software, not a lock. The open password is what actually protects the content.

Questions people ask

+What if I forget the password?

It can't be recovered. We never keep it. Keep your unprotected original until you're sure the password is saved.

+Which apps can open the protected file?

Any modern PDF reader that supports AES 256, including Adobe Acrobat, Preview on Mac, and browser PDF viewers.

+Can I protect a file that already has a password?

Unlock it first with its current password, then protect it again.

+Are my files kept on your server?

No. The file is processed in memory for this one request and the result is sent straight back to your browser. Nothing is written to storage and nothing is shared.

Also useful
More free PDF tools

Ready to fix your PDF?

Free, in your browser, and it takes about a minute. No account needed.

Choose a PDF