ConvertFlow

Password-protect a PDF

Encrypt a PDF with a user password and set permission flags.

Password-protect a PDF: Encrypt a PDF with a user password and set permission flags. Add your file to the tool above, apply it, and download the result — free, in any browser, with no sign-up.

About this tool

Adds standard PDF encryption with a user (open) password and optional owner password restricting printing and copying. Encryption is applied in the browser with a pdf-lib fork.

How to use Protect PDF

  1. 1. Add your file

    Drop your file onto the Protect PDF workspace above, or click to browse for it.
  2. 2. Choose the options

    Adjust the settings for protect pdf — the defaults work for most files.
  3. 3. Download the result

    The result is generated in your browser — nothing is uploaded. Click Download to save it.

Frequently asked questions

Is Protect PDF free to use?

Yes. Protect PDF is completely free with no watermark, no account, and no file-count limit.

Are my files uploaded to a server?

No. Processing happens in your browser using WebAssembly and the Canvas API. Your documents never leave your device.

Which browsers are supported?

Any modern browser — Chrome, Edge, Firefox, or Safari. No extension or desktop app is required.

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