Password protect a PDF
Lock a PDF with a password so that only the people you share it with can open it.
or drop a PDF anywhere on this page
Accepts PDF
Your password is used on this device and never sent anywhere.
- Nothing uploaded
- No account
- Checked after processing
- Free
How to password protect a PDF
Protecting a PDF with a password keeps it private when it is sent by email, stored in a shared folder or carried on a USB stick. This tool encrypts your document with AES-256, the strongest encryption a PDF supports. Both the document and the password stay on your own device, which matters most for exactly the files you would want to protect.
- Choose a PDF file, or drop a PDF anywhere on this page.
- Type a password, then type it again to confirm it.
- Select Protect PDF. The locked document is checked, then saved to your device.
Why it is better on your device
- Private by design. Your files never leave your device. There is no copy on a server to be kept, leaked or deleted later.
- No waiting. Work starts the moment you choose a file, because there is nothing to upload or download first.
- Checked before you get it. The locked document is opened twice by a second, independent PDF reader: once without a password, which must be refused, and once with your password, which must succeed. If the check does not pass, nothing is offered and your original stays exactly as it was.
- Free, with no account. No sign-up, no watermark added to your work, and it keeps working offline after your first visit.
Good to know
- Your password is never sent anywhere or kept. If you lose it, the document cannot be opened again, by anyone.
- PDF readers that are many years old may not open a document locked with AES-256.
Questions
Frequently asked questions
How do I password protect a PDF?
Choose your PDF, type a password twice and select Protect PDF. The locked copy is saved to your device, and anyone who opens it will be asked for the password.
How strong is the protection?
The document is encrypted with AES-256, the strongest encryption the PDF format offers. A long password that is hard to guess makes it stronger still.
Is my password sent anywhere?
No. The password is used on your device to lock the document and is then discarded. It is never sent or stored.
What happens if I forget the password?
The document cannot be opened again. Nobody can recover the password, because it was never stored anywhere. Keep a note of it somewhere safe.
Is my PDF uploaded to protect it?
No. The document is locked on your device and never leaves it.
Security