PDF schützen - Proteggi PDF

A PDF is open by default like a book - anyone who has the file can read, copy and print it. For a job application that may not matter, for sensitive paperwork it does. PDF Password puts a password over the file so it only opens with the correct key.

You choose between several encryption strengths. AES-256 is the current standard and the strongest option, AES-128 is a bit more compatible with older PDF viewers, and RC4-128 exists for very old software. In most cases you pick AES-256 and are on the safe side.

Beyond plain open protection you can set permissions. A user password demands the key already when opening. An owner password allows reading but blocks printing, copying or editing, depending on which boxes you tick. That way you release a document for viewing without someone simply copying the content out.

If you know the password of a protected file, the unlock mode reverses the process and saves the PDF without protection. Handy when you sent yourself an encrypted document and want to get rid of the password dialog on every open. A batch mode processes several files with the same password at once.

The tool uses a hybrid processing model. A single file protected with RC4-128 stays in the browser. For AES-128, AES-256 and unlocking, the PDF and password are sent to the tool server over an encrypted connection. qpdf processes them in a private, short-lived working directory; the work files are deleted at the end of the request and are not saved to your file cabinet or account.