Protect PDF
Add a password and encrypt your PDF file
Add a password to your PDF so only people you trust can open it. Your file is encrypted with AES-256.
- AES-256 encryption
- Done in seconds
- Free, no sign-up, no watermarks
How it works
How to password protect a PDF
- 01
Drop your PDF into the upload area, or click to browse.
- 02
Type a password, then type it again to confirm.
- 03
Click Encrypt PDF.
- 04
Download your protected PDF.
Strong encryption
Your PDF is encrypted with AES-256, so it cannot be opened without the password.
Password strength meter
See at a glance whether your password is weak, medium or strong before you encrypt.
Done in seconds
Your protected PDF is ready to download in a few seconds.
Questions
Frequently asked
What happens if I forget the password?
CrestPDF does not store your password, so it cannot be recovered. Keep it somewhere safe.
How secure is the encryption?
Files are encrypted with AES-256. Use a long password with a mix of words, numbers and symbols for the best protection.
How long does it take to password protect a PDF?
Usually just a few seconds. Very large files can take a little longer.
Is Protect PDF free?
Yes. It is free to use, with no sign-up and no watermarks added to your files.
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