Password-protect a PDF
Lock a PDF so nobody can open it without the password. 256-bit AES encryption, done on your own device.
Choose the PDF you want to protect
or drop it here
Processed in this browser: your file is never uploaded to any server. Turn on airplane mode once the page has loaded and it keeps working. Check it yourself
How to use it
- Choose the PDF.
- Type the password twice.
- Tap “Protect and download”. The new file asks for the password when it opens.
Good to know
- If you forget the password, there’s no way to get it back. We never store or see it: the encryption happens in your browser. Keep it somewhere safe.
- We use 256-bit AES, the encryption of current PDFs. Today’s readers open it: Acrobat, the Chrome and Edge viewers, and phone apps. A very old reader may not.
- A long password protects better than a strange one: three or four words together beat “P@ss1”.
- If you email the PDF, send the password another way (a text message or a call).
“Block copying and editing” asks PDF readers to disable those actions. Most respect it, but it isn’t strong protection: what really protects the file is the password to open it.
Questions
How secure is it?
With a good password, very: 256-bit AES can’t be broken by trying passwords in any reasonable time. The weak point is usually the password, not the encryption.
Can I remove the password later?
Yes, if you know it: use Unlock PDF.
Other tools
Updated