Protect PDF
Encrypt the file with a password so only people you choose can open it
Drag a PDF here
Or click to select a PDF from your device
✓
Protected copy ready
How to password-protect a PDF
- Add the file Drop the PDF you want to lock.
- Choose a password Type it twice, and keep it somewhere safe.
- Set the permissions Decide whether readers may print or copy text.
- Download The new file asks for the password every time it is opened.
What this protection does and does not do
- The file is encrypted with AES-256, the current standard for PDF encryption.
- Printing and copying restrictions depend on the reader app; some tools ignore them.
- A password protects access, not the content after someone opens the file legitimately.
- There is no recovery: if you lose the password, the file cannot be opened by PDFHelix or anyone else.
Frequently Asked Questions
Is the password sent anywhere?
No. The password and the file stay in your browser, and the encryption runs on your device.
Can I remove the password later?
Yes, if you know it: open the file with Unlock PDF and save an unrestricted copy. Without the password there is no way in.
Which apps can open the protected file?
Modern readers support AES-256, including current versions of Acrobat, Chrome, Firefox, Safari, Preview and most mobile PDF apps.