How to protect a PDF
Choose the file
Pick a PDF or drop it on the box.
Type a password
Type it twice to be sure; you can also limit printing, copying and editing.
Protect and download
Press “Protect and download” and keep the password somewhere safe.
Before you start
Passwords can’t be recovered: if you forget it there is no way to open the file, here or anywhere else, so keep an unprotected copy or the password somewhere safe.
Use a strong password: 10 or more characters mixing letters and numbers, or a phrase of several words. Short common words can be guessed.
Send the password another way: if you email the file, send the password by text message or a call, not in the same email.
FAQ
How strong is the protection?
The file is encrypted with AES-256 (the PDF 2.0 revision), the strongest encryption PDF supports, which every modern reader opens: Adobe Acrobat, web browsers and phone apps.
What’s the difference between the open password and the limits?
The open password really encrypts the file; it can’t be read without it. The limits ask reader apps not to print or copy; well-known apps respect them, but some may ignore them.
Do you see my password?
No. Encryption runs inside your browser with the open-source qpdf engine; neither the file nor the password is sent anywhere.
How do I remove the password later?
Use Unlock PDF with the password.
Are my files uploaded?
No. The file is read and processed inside your browser. It is never sent to a server and we keep no copy.