PDF tool
Password-protect a PDF
Protect a PDF with a password for free, so it cannot be opened without it. Encrypted in your browser; we never upload your file and never see your password.
Drop a PDF here
Never uploaded · processed in this tab
What this tool does
Protect PDF locks a PDF with a password. Anyone who opens the file is asked for it, in any PDF reader, on any device. The file is encrypted with AES-256, the strongest method the PDF standard offers, so the content cannot be read without the password.
How to password-protect a PDF
- Choose a PDF, or drop it onto the box above.
- Type a password, then type it again to make sure.
- Select Protect PDF, then download the locked copy.
- Send the password to the recipient a different way than the file, for example by text message.
What happens to your file and password
We never upload your file, and your password never leaves this tab. The encryption runs inside your browser, on your own device. We do not store the password, so we cannot tell you what it was later.
What it cannot do
- It cannot recover a forgotten password. Keep a note of it.
- A password protects the file, not what someone does after opening it: they can still copy or print it.
- It cannot protect a file that already has a password. Unlock it first with the password you have.
- Very old PDF readers, from before 2006, cannot open AES-256 files.
Frequently asked questions
It encrypts the file with a password you choose. Anyone who opens the PDF in a standard reader has to enter that password before they can see the pages.
We cannot recover it. The password is never sent to us or stored by us, so keep it somewhere safe before you share the protected file.
No. We never upload your file, and the password is used only in your browser to encrypt it on your own device.