Stop fake signups from draining your AI budget.

Up to 40% of signups use burner emails to abuse free tiers. Every fake account burns real tokens. Validate emails at the door and stop paying for fraud.

Start Blocking Fakes
100 free validations/mo|One API call per signup
signup-handler.ts
import { BigShield } from 'bigshield';

const shield = new BigShield('ev_live_...');

// Block fake signups before they cost you tokens
const result = await shield.validate(formData.email);

if (result.recommendation === 'reject') {
  return res.status(400).json({
    error: 'Please use a real email address'
  });
}

// Safe to provision AI credits
await createAccount(formData.email);
40%
of signups can be fake
using burner or disposable emails
$0.01–0.10
wasted per fake user
in AI tokens, API calls, and compute
<100ms
to catch them
validate at signup, block before provisioning
945+
burner domains tracked
and growing — updated continuously

See what your signup form is missing

Try a burner email like test@mailinator.com and watch it get flagged instantly. Then try your real email.

Add to your signup flow in 5 minutes

One API call between “Submit” and “Create Account.” That's it.

01

Install

One package. Drop it into your signup flow in minutes.

02

Validate at Signup

Check every email before you provision accounts or AI credits.

03

Block or Allow

Reject burners and fakes. Only onboard real users who won't waste your tokens.

install.sh
npm install bigshield
validate.ts
import { BigShield } from 'bigshield';

const ev = new BigShield('ev_live_...');

// In your signup handler
const result = await ev.validate(req.body.email);

if (result.recommendation === 'reject') {
  // Burner or fake — don't waste tokens
  return res.status(400).json({
    error: 'Please use a valid email address'
  });
}

// Real user — safe to provision AI credits
const user = await createAccount(req.body.email);
await allocateTokens(user.id, plan.tokens);
response.json
{
  "id": "val_a1b2c3d4",
  "email": "user@example.com",
  "status": "completed",
  "risk_score": 82,
  "risk_level": "low",
  "recommendation": "accept",
  "signals": [
    {
      "name": "email-format",
      "tier": "tier1",
      "score_impact": 10,
      "confidence": 1.0,
      "description": "Email format is valid"
    },
    {
      "name": "domain-reputation",
      "tier": "tier1",
      "score_impact": 15,
      "confidence": 0.95,
      "description": "Well-known email provider"
    },
    {
      "name": "mx-records",
      "tier": "tier1",
      "score_impact": 10,
      "confidence": 0.9,
      "description": "Valid MX records found"
    }
  ]
}

Built to stop the signup tricks that drain your wallet

Burner emails, disposable domains, freshly-registered fakes. We catch them all before they cost you a cent.

Signup Fraud Detection

Catch fake accounts at the door. Stop users from spinning up burner emails to farm your free tier.

Protect Your AI Spend

Every fake signup burns real tokens. Validate first, provision later — save 20-40% on wasted compute.

Under 100ms

Fast enough for inline signup validation. Users won't notice. Your budget will.

945+ Burner Domains

Mailinator, Guerrilla Mail, Tempmail — all caught instantly. Database updated continuously.

Risk Score 0-100

Not just pass/fail. Granular scoring lets you gate free tiers, require verification, or block outright.

Domain Intelligence

MX records, domain age, provider classification. Spot freshly-registered domains used for abuse.

Smart Caching

Same domain checked twice? Cached. You only pay for unique lookups, not repeat abusers.

Batch Cleaning

Already have a user list? Validate up to 100 emails per request. Find the fakes you're already paying for.

TypeScript SDK

npm install, import, call. Full type safety. Drop into Next.js, Express, or any Node backend.

Costs less than one fake user

A single abusive signup can burn $5-50 in AI tokens. Pay pennies per validation to save dollars per fraud.

Free

$0/forever

Test it on your signup flow. No card needed.

  • 100 validations/mo
  • 10 requests/min
  • Batch size: 5
  • Tier-1 signals
  • Community support
Start Free

Starter

$29/month

For apps starting to see signup abuse.

  • 5,000 validations/mo
  • 60 requests/min
  • Batch size: 25
  • Tier-1 & Tier-2 signals
  • Email support
Get Started
Most Popular

Pro

$99/month

For production apps bleeding AI tokens to fraud.

  • 50,000 validations/mo
  • 200 requests/min
  • Batch size: 100
  • All signal tiers
  • Webhooks & priority support
Go Pro

Enterprise

Custom

For platforms where abuse = existential cost.

  • 1M+ validations/mo
  • 1,000 requests/min
  • Batch size: 100
  • All signal tiers + custom
  • Dedicated support & SLA
Contact Sales