Smart Converter Pro
Smart Converter Pro

Protect PDF

Add a password and encryption to keep your PDF private. 100% free, secure and no sign-up required.

In-browser conversion coming soon

Real password protection needs proper AES encryption, which we won't fake with a weaker substitute. We're working on bringing true encryption to the browser.

About Protect PDF

Add a password and encryption to keep your PDF private. Everything runs through our fast, private pipeline — free, with no watermarks and no account needed.

How to use Protect PDF

  1. 1

    Upload your file by dragging it into the box above or clicking to browse — files up to 100MB are supported.

  2. 2

    Protect PDF starts automatically and runs securely in your browser, so your files never leave your device.

  3. 3

    Preview the result, then click Download to save the converted file.

Protect PDF online — free and private

Add a password and encryption to keep your PDF private. Everything runs through our fast, private pipeline — free, with no watermarks and no account needed.

Unlike most online PDF services, this tool processes your document directly in your browser whenever possible — your files aren't parked on someone's server, there's no queue, no watermark and no page limits. It works on any device with a modern browser, including phones and tablets.

Frequently Asked Questions

Is Protect PDF free?

Yes, Protect PDF is completely free with no watermarks or sign-up.

Are my files safe?

Yes. Files are processed securely and deleted automatically shortly after processing.

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