What's the difference between an open password and a permissions password?

An open password is required to view the file at all. A permissions password lets anyone view but restricts printing, copying or editing. The planned tool supports both.

Can I password-protect a PDF today?

Yes — use the Protect PDF tool on this page. Add your PDF, set a password, and download the encrypted file. Everything runs in your browser, so your document never leaves your device.

Protect PDF with Password — AES-256 Free

100% FREE • NO SIGN-UP • WORKS IN YOUR BROWSER

Every tool you need to work with PDFs in one place

Our tools are 100% FREE and easy to use! Merge, split, compress, convert, rotate, and watermark your PDFs with just a few clicks — no uploads, your files never leave this device.

Everything runs locally in your browser using open-source PDF engines. Files are processed on your device and are never sent to a server.

Protect PDF — Password-Protect PDFs Free

Lock your PDFs with a password so only the right people can open, print or edit them. The counterpart to Unlock PDF: lock files you send out, unlock ones you receive.

Protect PDF is live — free AES-256 encryption

Set a password on any PDF right here in your browser. We encrypt it with AES-256 — the same standard banks use — so only people with the password can open it. Your file and your password never leave your device.

Tips for best results

Use a 16+ character passphrase — encryption is only as strong as the password.

There is no password reset: store it in a password manager before protecting.

Today, LibreOffice and Adobe Acrobat both password-protect PDFs natively.

Share the password through a different channel than the file itself.

Frequently asked questions

What does the password do?

Anyone opening the file must enter the password — no password, no access. Use a strong, unique password and share it through a different channel than the file itself.

How strong should my PDF password be?

Use a long, unique passphrase — 16+ characters with mixed types. PDF encryption is only as strong as the password.

Can I password-protect a PDF for free?

Yes — right here, free, with no sign-up. The encryption happens in your browser, so nothing is uploaded.

What if I forget the password later?

There's no backdoor — a forgotten strong password means the file stays locked. Store passwords in a password manager.