Protect PDF

Add password encryption to a PDF for free.

or drop your file here

Processed securely on our server, then auto-deleted within the hour.

Put a password on a PDF so it cannot be opened without it. Protect PDF encrypts the document with the password you choose, and the file you download is the protected copy. This one runs on our server — encryption needs a real PDF engine, so the upload is processed there and not kept afterwards. Choose a password you will remember: there is no recovery, and every tool here that needs to read an encrypted file will need it typed in first.

How to use Protect PDF

Click "Select PDF file" and choose the PDF to lock.
Type a password of at least four characters. Use something you can retype exactly — the file cannot be opened later without it.
Click "Protect PDF" and wait for the encrypted copy.
Download it and open it once to confirm the password prompt appears and your password works.

Who it is for

Protect PDF is for sending a document that should not be readable if the file itself is forwarded or a link leaks. A payroll summary, a signed settlement, a client's medical letter, a draft that is not for circulation — anything where the wrong reader is a real risk rather than an inconvenience. It is also the honest way to send a document where the recipient already expects a password, because a password they have to ask you for proves the file came from you.

How it works

The file is uploaded, encrypted with the password you choose, and the encrypted copy is returned. The unencrypted upload is not kept.
Encryption is applied by a real PDF engine on the server rather than by a browser library, which is what makes the resulting file open correctly in every reader that supports standard PDF encryption.
The password is set by you, not generated, so the recipient can be told it through a different channel than the file itself.

What it cannot do

There is no password recovery. Lose it and the file is unreadable, permanently, by anyone including us.
This runs on the server, so the document and the password are uploaded for processing. If that is unacceptable for a document, no tool here can encrypt it locally instead.
Permissions that forbid printing or copying are a separate flag that many third-party readers ignore, so treat the password as the security and the permissions as a request.
An already-encrypted file must be unlocked before it can be re-encrypted.

Frequently asked questions

What happens if I forget the password?

The file cannot be opened, and there is no reset. The encryption is real, which is the point — it also means nobody here can recover it for you. Store the password in a manager before you send the file on.

Does protecting a PDF stop people copying or printing it?

It stops them opening it without the password, which is the meaningful protection. Permissions that restrict printing or copying exist as a separate flag, and third-party readers widely ignore them — so treat the password as the security and the permissions as a courtesy.

Is my file uploaded?

Yes. This is a server-side tool, because encryption needs a real PDF engine rather than a browser tab. The file and the password are sent for processing, the encrypted result comes back, and the upload is not kept. If a document is too sensitive to leave your device, the browser tools here — Sign PDF, Redact PDF, Annotate PDF — never upload anything, but none of them can encrypt.

Can I remove the password later?

Yes, if you know it — Unlock PDF removes it from a file you can open. If you do not know it, nothing can.

Which PDFs cannot be protected?

A file that is already encrypted has to be unlocked before it can be re-encrypted with a new password. Run Unlock PDF first on a file you own.