Verisoul Docs

Backend Integration

Once Verisoul's ZeroFake SDK is initialized it takes care of monitoring each account and continuously calculating risk throughout the account lifespan.
If your app is ready to get a risk prediction, you can use Verisoul's API to get real time risk associated with the account. You must link the tracking_id from the client with your auth_id on the backend with a call to Verisoul's API.
After linking the tracking_id and auth_id both identifiers can be used to query the API at any time for a risk score.
ZeroFake will return relevant risk metadata and a ZeroFake score for that account. Here is an example
"auth_id": "abc123",
"decision": "Real",
"zerofake_score": 0.10,
"multi_accounting_probability": 0.25,
"bot_probability": 0.06,
"general_risk_probability": 0.18,
Your app can use this real time risk prediction to dynamically alter the friction the user account experiences. This can be through third party services like reCaptcha or Verisoul's ZeroKYC product.


try {
// Get a real time prediction
let response = await fetch('', {
method: 'POST',
headers: {
'x-api-key': {VERISOUL_API_KEY}
body: JSON.stringify({
auth_id: {ACCOUNT_ID},
tracking_id: {TRACKING_ID},
if (!response.ok) {
throw new Error(`failed to get prediction: ${response.status}`);
let {decision} = await response.json();
if (decision === 'Fake') {
// do something
} else if (decision === 'Suspicious') {
// do something else
} else {
// user is real!
} catch (err) {