Protect PDF
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About Protect PDF
Drop an unlocked PDF. Type a password twice. Protect encrypts the file so a reader must enter that password to open it. The preview below uses the password you just typed so you can confirm it works before you download.
This page cannot open a file that is already encrypted. Unlock it elsewhere, then protect it here if you want a new password. We cannot recover a password you forget. Keep an unlocked copy of the original.
How to use Protect PDF
- 1Drop a PDF. Use an unlocked file.
- 2Create a password. Type it twice. They must match.
- 3Click Protect PDF. The preview opens with the password you entered.
- 4Download and verify. Open the download in Chrome or Acrobat and confirm it asks for the password.
Limits and privacy
Encryption runs in this browser. The password is not sent to aiaq.io and is not stored. Each file can be 25MB on a phone or 50MB on a desktop. No account.
FAQs
- What kind of password is this?
- An open password. Anyone who opens the file must type it to view the PDF.
- What if I forget the password later?
- We cannot recover it. Keep an unlocked copy of the original before you protect a file you still need.
- Can I protect a file that is already locked?
- No. This page will not open it. Unlock it first, then drop the unlocked file if you want to set a new password.
- Does aiaq.io see the password?
- No. The password stays in this browser for encrypting and for the local preview.
- Is a short password blocked?
- No. Weak passwords still encrypt. Use a long unique password anyway.