From a browser check
to your decision.

InstantBlock runs a check in the visitor's browser, evaluates the result, and returns a signed token. Your server verifies that token before completing the protected action.

Read the integration guide Create an account

Three connected steps.

The browser gathers evidence; InstantBlock produces a verdict; your application decides whether to continue.

01Visitor browserStarts a protected action

02InstantBlockChecks context and issues a verdict

03Your applicationVerifies the token and decision

Put a check exactly where it helps.

Use verification before a meaningful action, such as submitting a form or creating an account. You choose the point in your workflow.

Start a fresh challenge

The browser requests a challenge for your public sitekey and runs the client-side checks, including a WebAssembly verifier.

Evaluate the session

InstantBlock considers multiple signal groups and can request a follow-up challenge when more confidence is needed.

Check the token server-side

Your application validates the token signature, expiry and decision using the site secret. Only an accepted decision should allow the action.

A public key in the browser. A private secret on the server.

Use the sitekey to run the browser check. Keep the site secret only on your backend. The token travels with the action you want to protect.

This is a short illustration. The documentation includes the complete token validation example and current endpoint details.

Browserillustrative

import { runChallenge } from
  '<your-engine>/client/api.js';

const { token } = await runChallenge({
  sitekey: 'IB-S-…'
});

// Send token with the action to your server.

Designed for a considered rollout.

Does every visitor see a challenge?

No. A follow-up challenge is one possible path for uncertain sessions, rather than the default presentation for every visitor.

Where is the final access decision made?

In your application. Verify the token on your server and check that its decision is accept before continuing.

Can I inspect what happened?

The dashboard shows site activity and recent verification outcomes so you can review traffic during rollout.

Start with one protected action.

Create a site, add the browser check and verify the token in your backend.

Create an account View docs

From a browser check to your decision.