Encrypt sensitive PDFs before they go out by email or onto shared drives. PDF Converter uses QPDF to apply AES-256 encryption – the strongest standard PDF encryption – and lets you restrict printing, copying and editing for people who open it.
How to password protect a PDF
- Add the PDF to protect.
- Enter a strong password and choose permissions.
- Encrypt and download. Share the password through a different channel.
Good to know
- AES-256 requires a reader from roughly 2008 or newer (Acrobat 9+, all modern browsers and apps).
- Permission restrictions are honoured by mainstream readers but cannot technically stop determined users once the file is open. The open password is the real protection.
- PDF Converter never sees or stores your password.
Frequently asked questions
How secure is AES-256 PDF encryption?
With a long, random password it is considered very strong. Weak passwords can be guessed, so use at least 12 characters.
What if I forget the password?
There is no recovery. Keep an unencrypted copy somewhere safe.
Can I remove the password later?
Yes, with Unlock PDF, as long as you know the password.