Bot protection that
respects your users

Proof-of-Work captcha. No tracking, no cookies, no image puzzles. Drop in a script tag and you're done.

Zero config

One script tag, one API key. Your users solve a tiny computational puzzle — no clicking fire hydrants.

Privacy-first

No cookies, no fingerprinting, no tracking pixels. Just math.

Easy integration

Works with any form. Drop in the widget, verify on your server with one API call.

Three steps to protect your forms

1

Add the script tag

<script src="https://captcha.example.com/sdk.js"
  data-key="sc_live_abc123"></script>
<div id="scaptcha"></div>
2

User clicks the checkbox

Their browser solves a small proof-of-work puzzle in the background. Takes about a second.

3

Verify on your server

const res = await fetch("https://captcha.example.com/api/v1/verify", {
  method: "POST",
  headers: { "Content-Type": "application/json" },
  body: JSON.stringify({
    key: "sc_live_abc123",
    ...captchaFields
  })
})