How to password protect a PDF

Updated October 11, 2026

A password is the simplest way to keep a PDF from being read by whoever ends up with it: the wrong recipient, a shared inbox, a lost USB stick. Send the password by a different route than the file, or the lock does little.

What a password does and does not do

Password Protect locks a PDF so it cannot be opened without the password. That is all it does. It does not limit printing, copying or editing, because anyone who can open the file can do all of those. If you want those limits as well, see the section on permissions below.

Lock a file

  1. Open Password Protect and add your PDF.
  2. Type the password people will need to open it.
  3. Click Protect PDF. The encryption happens in your browser.
  4. Download the protected copy.

The tool uses AES-256, which is part of the PDF standard, so current PDF readers ask for the password and open the file once it is entered. Your file and your password are not sent anywhere or stored.

Choosing and sharing the password

Use a long phrase rather than a single word, avoid names and dates, and do not put the password in the same message as the file. Send it by text message, in a call or through a different app. A locked file sitting next to its key in the same inbox is not locked.

PDFLocal does not accept commas or equals signs in a password, so pick a phrase without them.

There is no recovery. Because nothing is stored on a server, nobody can reset a forgotten password for you. Keep a copy of the unprotected original somewhere safe.

Letting people read but not copy

Encrypt with Permissions adds the rules. You switch printing, copying text, editing and annotations on or off. It takes a password to open the file, which is optional, and an owner password as well, which protects the rules themselves. If you leave the owner password empty, the rules apply to everyone who opens the file and nobody can change them afterwards.

These permissions are instructions that a PDF reader chooses to follow. Reputable readers do, but a tool built to ignore them can get around them. Use permissions to discourage casual copying, and use a password to open the file when the content has to stay private.

Taking a password off

If you need to remove a password you already know, Remove Password does it. It asks for the current password, because the file has to be opened before it can be rewritten without one.

All three tools here are Pro tools with one free trial each. The trial output is watermarked, so use it to test on a real file and then send the clean copy. See the Pro page.