PDF tool · Runs 100% in your browser
Protect PDF
Lock a document before you send it. Set a password and the PDF is encrypted with AES-256, the same standard offices and banks rely on.
Drop a PDF file here
or click to choose it from your device · PDF only · processed locally
Add a PDF file to protect.
How to protect pdf
- Add your PDF. Contracts, statements and scans are the usual candidates.
- Set a password. Type it twice. It is never sent anywhere — there is no server to send it to.
- Press Protect PDF. The encryption engine runs in this tab and locks the file.
- Download and share the password separately — never in the same message as the file.
Good to know
Protection here is real cryptography (AES-256 via the qpdf engine), not a cosmetic flag: anyone opening the result is asked for the password by every standard reader. That also means a forgotten password is gone for good — we cannot recover it, because we never see it. Store it in your password manager before you share the file.
Frequently asked questions
How strong is the protection?
AES-256 with the password required to open the file at all. A long, unique password makes it practically unbreakable; a short one is only as strong as the password itself.
Can you recover my password if I forget it?
No — and that is by design. The password is used locally in your browser and never transmitted or stored anywhere.
Will protected files open in normal readers?
Yes. The encryption is the PDF standard, so Adobe Reader, browsers and phone readers all prompt for the password and open it.
Is the password sent to a server for processing?
Never. Both the file and the password stay inside this browser tab.
Keep going