Processed on your device — never uploaded

Protect PDF with a password

Some PDFs should not open for whoever finds them. Real AES-256 encryption, applied right in your browser — the password never exists anywhere but your head and your device.

Drop a PDF here or click to browse Tap to choose a file
PDF · encrypted locally · nothing uploaded

Real AES-256, not a "please don't open this" flag

This tool applies genuine AES-256 encryption — the same algorithm banks and governments rely on — so without the password the contents are mathematically unreadable, not merely hidden behind a setting a viewer can ignore. One password both opens and owns the file: send a contract, a medical report or client files knowing that only the person you gave the password to can read them.

Everything happens in your browser, which means the password is typed on your device, used on your device, and never transmitted, logged or stored anywhere. That is also the honest warning: there is no "forgot password" here — not with us, not with anyone. If the password is lost, the document is lost with it. Put it in a password manager before the file goes anywhere.

Frequently asked questions

How strong is AES-256, really?
It is the encryption standard used for classified documents and online banking. Without the password the contents are unreadable — there is no known practical attack against it.
Can I remove or change the password later?
Yes — our Unlock PDF tool removes it in seconds, as long as you know the password. Changing it is the same trick: unlock, then protect again with the new one.
What happens if I forget the password?
The document stays locked, permanently. Nothing is stored on any server, so there is nobody who could reset it — that is precisely what makes the protection real. Keep the password in a password manager.

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