Protect
Add a password to a PDF
Password-protect a PDF with AES encryption, free and with no installation. Your confidential files and passwords never leave your device.
- Files processed on your device
- No file size limit
- 100% free
How to password-protect a PDF
- 1Import the PDF you want to protect by drag and drop: encryption happens directly in your browser, and your password never passes through a server.
- 2Choose a strong password (at least 8 mixed characters) and confirm it; optionally set a separate owner password and fine-grained permissions (printing, copying, editing).
- 3Click “Protect PDF”: the document is encrypted with AES (PDF 1.7 standard) and downloaded immediately. Store the password safely — it cannot be recovered.
Frequently asked questions
Does the password pass through a server?
Never. Encryption happens entirely in your browser via WebAssembly: neither the file nor the password is ever transmitted online. That is a major difference from most PDF protection services, which receive both on their servers.
What kind of protection is applied?
AES encryption following the PDF 1.7 standard — the same used by professional software. You can set an open password, a separate owner password, and fine-grained permissions: printing (low or high resolution), text copying, editing, annotations and form filling.
What if I forget the password?
The document becomes permanently unreadable: we store nothing and there is no recovery procedure. Save the password in a dedicated password manager before encrypting, and keep an unprotected copy of the original somewhere safe.
What is the difference between the open password and the owner password?
The open password is required to read the document. The optional owner password grants full control: changing permissions or removing the protection entirely. If you don't set one, the same password plays both roles.