Protect a PDF with a password
Lock a document so it cannot be opened without a password. The file is encrypted with AES-128 — strong, and supported by every PDF reader in common use, including the one built into your phone.
Open Protect a PDF with a password
Free, no account, and your file is never uploaded.
How to password protect a PDF
- 1Choose the PDF you want to lock.
- 2Set the password that will be needed to open it.
- 3Protect, then download the encrypted file.
Worth knowing
- The password is never transmitted. Encryption happens in your browser. The password is not sent anywhere, not stored, and not recoverable by anyone here — including us.
- There is no way to recover it. That is the point of encryption, and it is worth saying plainly: if you forget the password, the document cannot be opened. Save it somewhere before you close the tab.
- AES-128, deliberately. AES-256 exists but older readers refuse it. AES-128 is strong enough for any ordinary document and opens everywhere, which matters when you are sending the file to someone whose software you cannot control.
- Encryption controls opening, not behaviour. A password stops someone opening the document. It does not reliably stop printing or copying once it is open — those permission flags are advisory and many readers ignore them.
Related PDF tools
They are all in the PDF workspace, and the rest of the free tools — invoices, QR codes and file compression — need no account either.