Sending a contract, a payslip, medical results or anything with personal information? Adding an open password means only someone who knows it can read the file, even if the email is forwarded or the document ends up on a shared drive.
Protect a PDF
- Open Protect PDF and drop your file in.
- Enter a strong password and confirm it.
- Click Protect PDF. The encrypted file downloads - anyone opening it will be asked for the password.
Why AES-256
Our Protect tool encrypts with AES-256, the same algorithm banks and governments rely on. Older PDF passwords used weak 40-bit or RC4 encryption that modern computers crack in minutes; AES-256 is not brute-forceable in any practical timeframe. The strength of your protection then comes down to one thing: the password you choose. Use a long passphrase, and share it through a different channel than the file itself (a text message, not the same email).
Removing a password
If you have a PDF that keeps asking for a password you already know and you want to stop being prompted, use Unlock PDF. It removes the protection - but only when you supply the correct current password. It cannot open a file you are locked out of; that is by design.
How your file is handled
Protect and Unlock use the qpdf encryption engine on our server. Your PDF travels over an encrypted HTTPS connection, is processed in a temporary folder, streamed back to you, and deleted immediately - never stored, never logged. There is also no back door: if you forget a Protect password, not even we can recover the file.