Need to secure a PDF with a password? Adding password protection encrypts the PDF so only people with the password can open it.
Open Fourmeld PDF Tools
Go to fourmeld.com/pdf-tools — works on any browser, no login needed.
Upload your PDF
Click Upload and select your PDF file from your device.
Set your password
Enter the password you want to use to protect the PDF. Choose the encryption level (128-bit or 256-bit AES).
Download the result
Click the action button and download your processed PDF instantly. No watermark.
Tips
- Use a strong password with letters, numbers and symbols
- Save the password somewhere safe — there is no password recovery for encrypted PDFs
- 256-bit AES encryption is the most secure option available
Password Protect PDF Free — Free, No Signup
Works on desktop and mobile. No software download needed.
Try Fourmeld PDF Tools Free →FAQs
How strong is PDF password protection?
256-bit AES encryption is the industry standard and is very difficult to crack with a strong password.
What if I forget the password?
There is no password recovery — keep your password in a secure location.
Can I remove the password later?
Yes — use the PDF unlock tool to remove the password (you'll need the current password to unlock it).