Simple, transparent pricing

A CAPTCHA asks the human to prove themselves by solving a puzzle. Proof-of-work asks the device to prove itself by spending a small, measurable amount of CPU. It’s invisible to the visitor and expensive for an attacker to repeat thousands of times.

It makes mass automation costly. A single legitimate submission costs a few milliseconds; submitting a form 100,000 times costs an attacker real compute time and money. Combined with rate limits and server-side verification, it removes the economic incentive for spam and credential stuffing.

No. The work runs in the background while the visitor fills out the form, and the difficulty is tuned so it completes in well under a second on a typical device. Most users are verified before they reach the submit button.

Yes. stopbot does not set cookies, fingerprint devices, or send personal data to third parties. The challenge and proof are anonymous tokens, so there is nothing to consent to and nothing to leak.

Because there is no visual or audio puzzle, there is no accessibility barrier. The widget is keyboard-operable and screen-reader friendly, and the verification happens without any required user action.

Add one script tag to your page, drop in the widget, and verify the returned token with a single API call on your server. We provide copy-paste examples for HTML, React, Vue and Laravel in the docs.