Files tool
Protect or Unlock a PDF with a Password
Choose a PDF to add a password, or remove its password by entering the current password.
About this tool
Protect or Unlock a PDF with a Password made simple.
The file is processed on your device with a local QPDF engine and is never uploaded. Protect mode uses AES-256 and asks for separate opening and owner passwords. Unlock mode requires the current password; this tool does not bypass or guess passwords. The input limit is 200 MB to reduce the risk of exhausting browser memory. Re-saving can invalidate digital signatures or change compatibility; keep the original and test the result in your PDF reader. Password strength and safe storage remain your responsibility.
Common questions
About Protect or Unlock a PDF with a Password.
How do I protect a PDF with a password?
Choose Protect PDF, enter different opening and owner passwords of at least eight characters, confirm the opening password and process the file. Save both passwords safely; they cannot be recovered here.
Can I unlock a PDF without its current password?
No. Enter the current password. This tool does not guess, crack or bypass passwords.