Protect PDF

Add a password to a PDF so it can only be opened with the password.

Information

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How to use Protect PDF

Set a password for the file, then share it separately from the document itself.

Why it helps

Uses real AES-256 encryption, so the protection holds up even if the file ends up somewhere it shouldn't.

No installation required

No standalone encryption or redaction software — protection happens right here in the browser.

Your files stay private

Especially relevant for this group: passwords and redacted content are processed only for your request, then gone.

Works on any device

Protect or unlock a file from any device — the encryption itself doesn't depend on your operating system.

Frequently asked questions

How do I add a password to a PDF?

Set a password for the file on the Protect PDF page, then share that password with recipients separately from the document.

What encryption does password protection use?

It uses real AES-256 encryption, so the protection holds up even if the file ends up somewhere it shouldn't.

Can I remove the password later if needed?

Yes — use Unlock PDF with the same password to remove the protection whenever it is no longer needed.

Join the world's largest companies

Employees at these companies use our products

NorthwindCobalt LabsVertex SystemsLumen GroupFieldstoneHalcyonRedwood PartnersMeridianAnchor & CoSolsticeNorthwindCobalt LabsVertex SystemsLumen GroupFieldstoneHalcyonRedwood PartnersMeridianAnchor & CoSolstice
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