Stop risky sessions before they become chargebacks.
Leonix combines device intelligence, IP intelligence, and server-side decisioning to help merchants detect suspicious sessions in milliseconds — with a single script tag.
From session to decision in milliseconds.
Leonix keeps the frontend minimal while moving all risk logic into a secure backend workflow.
Install one script
Add a single Leonix widget to your site with your tenant key. No SDK, no build step.
<script src="https://cdn.leonix.io/fraudwidgetV1.js" data-tenant-key="YOUR_KEY" data-api-base="https://..."> </script>
Collect trusted signals
The widget gathers device fingerprint, IP intelligence, and network context — then calls the Leonix API automatically.
Act on the decision
Leonix returns allow, review, or block with a risk score. Listen for it or let the widget handle it silently.
Live in under 5 minutes.
Paste the snippet below into your page — no signup required to try it. The key below gives you live access to the Leonix sandbox.
<script src="https://cdn.leonix.io/fraudwidgetV1.js" data-tenant-key="sk_live_30cb1de16ea2bbbde1148f4212415780" data-api-base="https://fraud-engine-prod-v3-794477191755.us-central1.run.app" data-fpjs-public-key="lybk8D8ZmpCZhhwO8gvZ" data-fpjs-endpoint="https://cdn.leonix.io/fpjs"> </script>
Optional — react to the decision
Listen for the fraudengine:ready event to take action on your page.
window.addEventListener('fraudengine:ready', (e) => {
const { decision, score, reasons } = e.detail;
if (decision === 'block') {
// hide checkout, redirect, etc.
}
if (decision === 'review') {
// trigger step-up auth
}
console.log('Risk score:', score);
console.log('Signals:', reasons);
});
{
"decision": "block",
"risk_score": 0.92,
"reasons": [
"R24_BAD_BOT",
"R28_ANTI_DETECT_OR_NODRIVER"
],
"agent": {
"scenario_type": "bot_signup",
"severity": "critical",
"recommended_action": "block_and_flag"
}
}
See Leonix score your session in real time.
Enter any email and password below — your device fingerprint is collected, scored against 30+ fraud rules, and a decision is returned in milliseconds. No data is stored.
Protect critical customer flows.
Leonix helps merchants monitor high-risk moments across the customer lifecycle.
Checkout protection
Detect suspicious sessions before payment authorization and reduce fraudulent transactions.
Account takeover
Identify unusual login patterns and session anomalies linked to compromised accounts.
Promo abuse
Detect coordinated activity across devices and IP ranges targeting promotions.
AI agent detection
Identify and interrogate LLM-powered browser agents — classify as legitimate bot, scraper, or fraud bot.
Shopify orders
Score every order via webhook. Cancel, tag, or flag risky orders automatically before fulfilment.
Any web flow
One script tag works on any HTML page — login, registration, checkout, or contact forms.
Request a demo.
See how Leonix helps your team evaluate and act on risky sessions with device intelligence and real-time decisioning.