How to password protect a PDF (and remove a password)

A password turns a PDF from something anyone can read into something only the people you trust can open. It is worth doing for bank statements, payslips, ID documents and anything containing personal information that you send by email. Here’s how to add a password on the devices most people use, and how to remove one when you no longer need it.

In your browser: Protect PDF

1. Open Protect PDF and choose your file.
2. Type a password twice. The strength meter shows whether it’s strong enough.
3. Optionally open Permissions to disallow printing, copying or editing.
4. Press Encrypt PDF and download the protected copy.

The file is encrypted with AES-256 on your own device using qpdf, a long-established open-source PDF library, so neither the document nor the password is uploaded.

On a Mac: Preview

1. Open the PDF in Preview and choose File › Export.
2. Tick Encrypt (on recent macOS versions, open Permissions to find the password option).
3. Enter and verify the password, then click Save.

On Windows: Microsoft Word

Windows can’t encrypt an existing PDF on its own, but if you are creating the PDF from a Word document you can protect it as you save:

1. In Word, choose File › Save As (or Save a Copy) and pick PDF as the file type.
2. Click Options and tick “Encrypt the document with a password”.
3. Enter the password and save.

For a PDF you already have, use a browser tool such as Protect PDF.

Choosing a password that actually protects you

PDF encryption is only as strong as the password. A short password can be guessed by software that tries millions of combinations, and modern AES-256 encryption doesn’t help if the password is “Smith2026”.

• Use at least 12 characters, or better, three or four unrelated words, such as copper-lantern-meadow-otter.
• Avoid names, birthdays, postcodes and anything printed in the document itself.
• Don’t reuse a password from an online account.
• Send the password by a different route from the file: a text message or phone call, not the same email.
• Keep it in a password manager. Nobody, including us, can recover a lost PDF password.

Open passwords and permission passwords

PDFs can have two passwords. The open password encrypts the file so it can’t be read without it; this is the one that matters for privacy. A permissions password lets a document open freely but asks reader software to block printing, copying or editing. Mainstream readers respect those restrictions, but they are not strong protection on their own. Our PDF privacy guide goes into more detail.

How to remove a password from a PDF

If you know the password and want to stop typing it every time, save an unlocked copy:

1. Open Unlock PDF and choose the protected file.
2. Enter the password.
3. Download the unlocked copy, which opens without a password.

On a Mac, you can also open the PDF in Preview, enter the password, and use File › Export without ticking Encrypt.

Removing protection is only appropriate for documents you own or have permission to change. Tools like ours need the correct password; they don’t crack or bypass encryption.

Before you encrypt

If the PDF contains a form, fill it in and flatten it first. If it is too large to email, compress it before adding the password, because encrypted files can’t be compressed further without unlocking them.