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How to protect or unlock a PDF with a password
Keep sensitive documents private, and open files you are allowed to open
Why add a password
Payslips, medical reports, tax papers and contracts often travel by email or messaging apps, where a stray forward can expose them. A password means that only people you give it to can open the file, even if the file itself is copied elsewhere.
Encrypting a PDF
- Open the Encrypt PDF tool and add your file.
- Type a password twice. Choose a long phrase rather than a short word, and avoid birthdays.
- Decide whether people may print, copy text or edit once the file is open.
- Download the protected copy. Text stays selectable after it is opened with the password.
Share the password through a different channel than the file. For example, send the PDF by email and the password by a phone call or message. A forgotten password cannot be recovered, so store it safely.
Unlocking a PDF
The Unlock PDF tool removes a password and any print, copy or edit restrictions from a file. If the file needs a password to open, type it in. The tool tries to remove the protection directly so text and quality are unchanged. For some newer encryption types it redraws each page as an image instead, which opens and prints freely but makes the text unselectable.
Only unlock documents that belong to you or that you have permission to change. The tool cannot guess or crack an unknown password.
Limits of PDF passwords
Standard PDF protection is good for everyday privacy but is not a replacement for professional security tools. Restrictions such as “no printing” are honoured by well-behaved apps but are weaker than the password that controls opening the file.
Everything described here runs inside your browser tab. Your files are not uploaded to a server, which you can confirm by turning off your internet connection after the page has loaded and running the tool again.
More help: all FirePDF guides.