How strong is PDF password protection?

It's standard PDF encryption, which is genuinely effective against casual access and is what every PDF reader supports. Like any password, its real strength is how hard yours is to guess — a long passphrase beats a short complicated one.

What's the difference between an open password and permissions?

The open password stops the file being read at all. Permissions apply after it's open, restricting printing, copying and editing. Readers enforce permissions voluntarily, so treat them as a clear instruction rather than a hard guarantee.

Protect PDF

Add a password to a PDF so it can't be opened without it, and choose what someone who does open it is allowed to do.

Drop your PDF hereor click to browse — up to 50MB

Your file is processed on our server and deleted the moment your download is ready — never stored, and cleared within the hour at the very latest.

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Why use this tool

Password required to open the document
Separately control printing, copying and editing
Standard PDF encryption that every reader understands
Your file and password are never stored

How it works

1Upload the PDF you want to protect.
2Choose a password and confirm it.
3Set what's allowed once it's open.
4Press Protect and download.

Protect PDF — frequently asked questions

The document cannot be opened, by you or by us — that's the whole point of encryption. We never see or store your password, so keep it somewhere safe before you send the file anywhere.

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