Protect PDF with a Password: free online tool
Protect PDF encrypts your document with a password. Anyone who opens the file must enter the password first. Encryption is applied in your browser.
Use Protect PDF with a Password now
Also searched as: password protect pdf · encrypt pdf · lock pdf · add password to pdf · secure pdf file
How to use Protect PDF with a Password
- Open Protect PDF and select your file.
- Enter and confirm a password.
- Click protect.
- Download the encrypted PDF and keep the password safe.
What you can do
- Password required to open the file
- AES-128 encryption
- Applied locally, so the password never leaves your device
Runs 100% in your browser · No upload · No sign-up · No limits
Privacy and where your file is processed
Runs 100% in your browser. Your file never leaves your device: no upload, no account and no usage limit.
Free usage limits
Free to use. In your browser: no account, no file-size limit and no usage limit. Advanced AI mode (our private GPU server): free account with 150 credits a month (1 credit per page for OCR and PDF to Word), files up to 50 MB and 100 pages. There is no paid tier.
Frequently asked questions
Can you recover a forgotten password?
No. The password is never sent to us and cannot be recovered. Keep a copy somewhere safe.
How strong is the protection?
The file is encrypted with AES-128. Strength still depends on choosing a long, unique password.