How to Password Protect a PDF
Email isn't a private channel by default — a message can end up forwarded, sitting in a shared inbox, or attached to a thread with more people on it than you intended. Password-protecting a PDF before you send it means that even if the file ends up somewhere you didn't plan, it can't actually be opened without the password.
What protecting a PDF does
Protect PDF encrypts the document with a password you choose, so the file can only be opened by someone who knows it. Anyone without the password can see the file exists — the name, the size — but not its contents.
How to password protect a PDF
- Open the Protect PDF tool.
- Upload the file you want to secure.
- Set a password.
- Download the encrypted PDF.
Choose a password that's long rather than clever. NIST's password guidelines recommend prioritizing length over arbitrary complexity rules, and a passphrase of several unrelated words is easier to remember than a jumble of symbols.
Share the password separately
A password only protects the file if it doesn't travel with it. Sending the PDF and the password in the same email defeats the point — anyone who intercepts one gets the other too. Send the password a different way: a text message, a phone call, or a separate email thread.
If you need to remove a password instead
If you're on the receiving end of a password-protected PDF and have the password but want an unprotected copy to work with, an unlock tool does the reverse of this — it removes the password once you've supplied it correctly.
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- How to Convert JPG to PDF Online for FreePhotos of a receipt, a signed form, or a whiteboard are easier to send as one PDF than as a pile of image files. Here's how.
- How to Convert a PDF to JPG (or PNG)Need a PDF page as a picture for a slide, a webpage, or a social post? Here's how to export pages as images.