How to Password Protect a PDF on Windows (Free)

About to email a bank statement, a signed contract, or a scan of your ID as a PDF? If it lands in the wrong inbox, you want it to stay locked. On a Mac you can encrypt a PDF with Preview in two clicks — but Windows has no built-in way to add a password to a PDF, and the free Adobe Reader cannot do it either (that feature is locked behind the paid Acrobat Pro).

Here is how to password protect a PDF on Windows 10 or Windows 11 for free, without installing anything.

Why your options on Windows are limited

• Microsoft Edge can view PDFs but cannot add a password
• The free Adobe Acrobat Reader cannot encrypt PDFs — that needs paid Acrobat Pro
• Microsoft Print to PDF creates a file but supports no encryption
• Windows provides no first-party PDF password tool at all

Password protect a PDF on Windows in your browser

Encrypting a sensitive file is exactly the job you want to keep on your own device. A browser-based tool locks the PDF using the encryption code running in your tab, so neither the document nor your password has to travel to a server:

1. 1Open the Protect PDF tool in Edge or Chrome on your Windows PC.
2. 2Drag your PDF from File Explorer into the upload area, or click to browse and select it.
3. 3Type a strong password — at least 12 characters with a mix of upper and lower case, numbers, and symbols.
4. 4Optionally restrict printing or copying with a separate permissions password.
5. 5Click protect and download the encrypted PDF, then keep your password safe.

The encrypted PDF will prompt anyone for the password before it opens, in any reader — Adobe, Edge, or a mobile app — because password protection is part of the PDF standard.

Use a strong, unique password

A PDF password is only as strong as the password itself. Avoid simple words or your birth year, and use a genuinely random string instead. Share the password through a separate channel — a text or a phone call, not the same email that holds the PDF — and never include it in the file name.

What a password does and does not protect

A password stops someone from opening the file without it, which is what you want for sending sensitive documents. It does not stop someone who already has the password from sharing it, so treat the password as the real access control. Keep an unlocked backup copy for yourself in case you forget the password, since a locked file you cannot open is no good to anyone.