How to Password Protect a PDF
Updated October 9, 2026
Some documents should not be opened by just anyone: a contract you are emailing, a payslip, a form with personal details. A password on the PDF means the file cannot be opened without it, even if it ends up in the wrong inbox.
Protect a PDF in 4 steps
- Open the Protect PDF tool and choose your file.
- Type a password of your choice. Use at least 4 characters, but longer is much better.
- Press Protect PDF.
- Download the new file and test it. Open it and check that it asks for the password.
Please read these limits
This tool runs in your browser, which makes it private and quick, but it works in a simple way. It saves each page as a picture inside the protected file. So:
- The text in the new file cannot be selected, copied or searched.
- The encryption is basic. It is good for keeping a casual reader out, but it is not meant for highly sensitive material such as medical or banking records. For those, use professional desktop software with strong encryption, and send the password by a different channel.
- If you forget the password, nobody can recover the file. Keep the original unprotected PDF safe.
How to choose a good password
- Use 12 characters or more. A phrase of several random words is easy to remember and hard to guess.
- Do not use birthdays, phone numbers or the name of the file.
- Never send the password in the same email as the PDF. Send it in a message, or tell the person by phone.
Removing a password later
If you own the file and know the password, use the Unlock PDF tool. Type the password and you get a copy without it. Only unlock files that you are allowed to open.
Frequently asked questions
Is my file uploaded to a server? No. The protection is added inside your browser.
Will the file be bigger? Possibly, because the pages are saved as pictures. You can make it smaller later with the Compress PDF tool, before you protect it.
Can I print the protected file? Yes, printing is allowed. The password is only needed to open it.