Protect a PDF with a password
Lock a PDF so that only people with the password can open it. The locking happens on your device.
Files never leave your device
Choose the PDF you want to protect.
Do not forget this password
If you forget this password, the file cannot be opened. We cannot recover it. Write it down or keep it in a password manager, and keep an unprotected copy of the original somewhere safe.
The PDF is locked with AES-256 encryption on your device. Your password and your file are never sent anywhere, and the password field is cleared when the job is done.
Working…
Keep this tab open. Large files can take a little while on a phone.
Done
Send it
Opens your phone's share menu — pick any app.
These open in a new tab. Your file is downloaded first; you attach it there yourself.
Your file is downloaded — attach it in the chat or email.
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How to use it
- Step 1: Tap the box and choose the PDF you want to protect.
- Step 2: Type a password twice. The strength hint helps you choose a good one.
- Step 3: Tap Protect with password and download the locked PDF.
Your files never leave your device
This tool runs entirely in your browser. Nothing is uploaded to a server, so your documents and photos stay private. It is free, has no watermark and needs no sign-up.
Frequently asked questions
How strong is the protection?
The file is locked with AES-256 encryption, the same strength that banks and governments rely on, using the standard PDF method (revision 6). A long password that is not easy to guess matters as much as the encryption itself.
What if I forget the password?
Then the file cannot be opened, and we cannot recover it. We never see your password, and there is no reset. Keep the password somewhere safe, and keep an unprotected copy of the original.
Does everyone need special software to open it?
No. Phones, browsers and normal PDF readers ask for the password and then open the file. Very old readers may not support AES-256, so tell the receiver if they have trouble.
Is my file or my password uploaded?
No. Both stay on your device. The encryption runs inside your browser, the password field is cleared when the job is done, and nothing is stored or logged.
Can I send the password in the same message?
It is safer not to. Send the file in one message and the password in another, ideally in a different app, such as a phone call or a text message.
Read the guide: How to Password-Protect a PDF Before Sending It →