Toolzed

Protect PDF - Add a Password

Add a password to your PDF with strong AES-256 protection, privately in your browser. The file and password never leave your device.

Runs 100% on your device - nothing you enter or upload leaves your browser.

Drop a PDF here or tap to browse

Protection happens on your device - the file and password are never sent anywhere

How to protect a PDF with a password

Drop your PDF, type the new password twice, and tap Protect and download. You get a copy of the same document that asks for the password when opened. Your original file is not modified.

Good to know

Frequently asked questions

How strong is the protection?
The copy is protected with AES-256 encryption, a widely used strong standard. Two honest limits: anyone who knows the password can remove it again (with the Unlock PDF tool here or similar software), and a short or common password can be guessed by password-cracking tools - pick a long one.
Can the password be removed later?
Yes - by anyone who knows it, using the Unlock PDF tool here or similar software. Protection keeps the contents private; it is not a permanent lock.
What if I forget the password?
This tool cannot recover it: nothing is stored anywhere, so there is nothing to retrieve it from. Weak passwords can also be cracked by other tools. Protect a copy, keep the original safe, and use a password you will remember.
Is my file or password uploaded?
No. Everything runs in your browser on your device. The file and the password you type never leave it.
The file is already password-protected - can I change the password?
Not directly. Remove the current password first with the Unlock PDF tool (you need to know it), then protect the unlocked copy with a new password.

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