SantaPDFTools
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Password-Protect a PDF Before You Share It

Payslips, contracts, medical reports: anything you wouldn't want opened by the wrong person deserves a password before it leaves your inbox. Lock PDF encrypts your file locally with AES-256, the same standard banks and government systems rely on.

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How it actually protects the file

The encryption runs through your browser's built-in Web Crypto API using your chosen password. Nobody, including us, ever sees that password. It never leaves your device.

Who tends to need this

Freelancers sending invoices with bank details, HR teams distributing payslips, anyone emailing a document with a name, ID number, or financial figure attached benefits from locking it before it leaves the outbox.

Frequently Asked Questions

What encryption standard does this use?

AES-256, via the browser's native Web Crypto API. It's a widely trusted, industry-standard algorithm.

Can I open a locked file in a normal PDF reader?

No. A file locked here needs the matching password entered through our Unlock PDF tool. It's not a standard encrypted-PDF format that generic readers understand.

Is my password sent anywhere?

No, the whole process happens locally in your browser.

What happens if I forget the password?

There's no way to recover the file. No backdoor, no master key. That's exactly what makes the encryption worth anything in the first place.

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