Guides ·
How to use Protect PDF
Protect PDF. Add AES-256 password protection. AES-256 (PDF 2.0, revision 6), the strongest standard PDF encryption.
The short answer
To password-protect a PDF, choose the file, type a password twice, choose what readers may do (print, copy, edit) and click Protect. The PDF is encrypted with AES-256 in your browser, so the password and document never leave your device.
It runs in your browser. What you enter is not uploaded.
How to use it
Choose your file with the upload box above, or drag and drop it onto the box.
Adjust the options; the preview updates as you change them.
Click the main button to process the file in your browser.
Download the result. Your original file is never changed or uploaded.
Limits worth knowing
How strong is the encryption? AES-256 (PDF 2.0, revision 6), the strongest standard PDF encryption. Adobe Acrobat 9 and later, Chrome, Edge, Firefox and macOS Preview open it.
What if I lose the password? It cannot be recovered. Keep a copy of the original file or store the password in a password manager.