Human verification for the modern web

Keep bots out.Keep users happy.

NexloLabs Verification is the CAPTCHA alternative with one script tag, eight challenge types, behavioral analysis and a risk score for every token. No tracking. No friction. No compromise.

< 60ms

verify latency

8

challenge types

0

tracking cookies

0–1

risk score

example.html
<script src="https://verify.nexlolabs.net/widget.js"></script>

<div
  class="nexlolabs-verification"
  data-sitekey="nlx_site_PUBLIC_KEY">
</div>

<script>
  NexloLabsVerification.render(
    ".nexlolabs-verification"
  );

  NexloLabsVerification.onSuccess(
    (token) => {
      // POST token + secret to
      // /api/challenge/verify
    }
  );
</script>
Human detected
score 0.97

Every challenge type you need

From the classic checkbox to invisible behavioral checks - pick the right level of friction for every form.

„I'm not a robot” checkbox

The classic checkbox with behavioral signals behind the scenes.

Image selection

Select all tiles containing the target letter. Rendered as SVG, no external assets.

Slider puzzle

Drag the puzzle piece to the missing spot. Fully deterministic, lightweight.

Math problems

Quick arithmetic checks for forms that need a low-friction proof.

Character codes

Distorted letter sequences - classic CAPTCHA, refreshed for the modern web.

Shape selection

Click every tile containing the requested shape. Easy for humans, hard for bots.

Vowel counting

Count the vowels in a word - a trivial check for people, expensive for bots.

Invisible verification

No interaction needed for trusted sessions. Behaves like a silent risk check.

Behavioral analysis

Mouse entropy, timing and interaction patterns feed a human-likeness model.

Risk score 0-1

Every token carries a score. Decide server-side how strict you want to be.

Privacy friendly

No tracking, no third-party cookies, no cross-site fingerprinting.

Live in three steps

From zero to protected forms in under five minutes.

1

Register your site

Create a site in the dashboard and get your public key (key) and secret key (secret).

npm run prisma:seed
# Site key:  nlx_site_...
# Site secret: nlx_secret_...
2

Add the script tag

One script. The widget renders automatically - no framework glue required.

<script src="https://verify.nexlolabs.net/widget.js"></script>
<div class="nexlolabs-verification" data-sitekey="nlx_site_..."></div>
3

Verify server-side

Your backend exchanges the token for a risk score. Accept or reject - it's your call.

fetch("https://verify.nexlolabs.net/api/challenge/verify", {
  method: "POST",
  headers: { "Content-Type": "application/json" },
  body: JSON.stringify({ token, secret }),
});
// { success, score, challengeId, hostname, expires }

Ready to verify?

Register your website, generate your keys and protect your forms with a single script tag.

Frequently asked questions

NexloLabs Verification is a SaaS platform under verification at verify.nexlolabs.net. Contact NexloLabs for pricing plans for high-traffic sites.