How to Password Protect a PDF for Free
To password protect a PDF for free, open it in Gold PDF, click Password in the Protect tab, type a password and save. The saved file is encrypted with AES-256 and anyone opening it must enter the password.
Quick steps
- Open the PDF and finish your edits.
- Choose Protect → Password and enter the password.
- Press Save as. Keep your working copy unprotected if you wish.
- Reopen the saved file to test the password prompt.
Choosing a strong password
Use at least 12 characters, ideally a passphrase of several unrelated words. Do not reuse passwords from email or banking, and do not send the password in the same message as the file.
What the password does and does not do
It encrypts the content so the file cannot be opened without the password. It does not hide the existence of the file, and it cannot protect against someone you gave the password to.
Sharing securely
Send the file and the password by different channels. For sensitive data also clear metadata first: how to remove metadata from a PDF.
Overview: Password protect a PDF.
Frequently asked questions
What encryption does Gold PDF use?
AES-256 password encryption when you save a protected PDF.
Can Gold PDF open a PDF if I forgot the password?
No. It opens protected files only when you enter the correct password.
How do I remove the password?
Open the file, choose Password, click Remove password and save a new copy.
Gold PDF — the free PDF editor for Windows
Edit text, redact for real, OCR scans, fill forms, sign and protect. Offline, no account, no watermark.