Protect PDF

Add a password to secure your PDF.

About this tool

Password Protect PDF — Encrypt Without Uploading

Add a password so only the right people can open the document. Everything runs locally in your browser — no upload, no sign-up, no watermark and no file size limit.

Open-Password Encryption

Set a password that must be entered before the PDF can be opened in any standard reader.

The Password Never Travels

Sending a file to an online encryption service means handing over both the document and its key. Here neither leaves your browser.

Works With Any Reader

Output uses standard PDF encryption, so Acrobat, Preview, Chrome and mobile readers all prompt for the password.

How to use it

  1. Drop the PDF you want to secure.
  2. Type a password under Set a password. The eye button shows what you typed, so you can check it for typos.
  3. Click Protect PDF. The file is encrypted on your device.
  4. Download the protected copy and test it once by opening it with the password.
  5. Send the password through a different channel than the file, for example by phone or text message instead of in the same email.

Frequently asked questions

Are my PDFs uploaded to a server?

No. Toolula processes the document inside your browser tab with pdf-lib and WebAssembly, so the file never leaves your device.

What happens if I forget the password?

The file cannot be recovered — store the password in a password manager before you share the document.

Can I only block printing or copying?

No. Toolula sets one password that is needed to open the file; there are no separate permission settings. Anyone with the password can print and copy.

Is it really free?

Yes. You can use every Toolula PDF tool for free, without an account. The free plan has fair-use limits; Toolula Pro, an optional plan, raises them and adds advanced features.