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Email Validation API for Developers

Validate and classify email addresses without SMTP probing. Single validates are free (0 credits); batch validate costs credits. Related helpers cover disposable checks, role accounts, normalize, and domain checks.

Features

What this API actually supports in production today.

  • POST /v1/email/validate (0 credits)
  • Batch validate for lists
  • Disposable and role checks
  • Domain / normalize helpers
  • Explicit: does not prove mailbox existence

Common use cases

  • Signup form hygiene
  • Cleaning marketing lists before send
  • Blocking disposable domains at registration

API endpoints

Base URL https://thefatbaby.com/api. Authenticate with Authorization: Bearer fb_live_YOUR_KEY.

MethodPathSummaryCredits
POST/v1/email/validateValidate one email0 credits
POST/v1/email/batch-validateValidate many emails2 credits
POST/v1/email/disposable-checkDisposable domain check0 credits
POST/v1/email/domain-checkDomain check0 credits

Examples

Primary endpoint /v1/email/validate · Single validate is free; batch validate is 2 credits by default.

cURL

curl -X POST https://thefatbaby.com/api/v1/email/validate \
  -H "Authorization: Bearer fb_live_YOUR_KEY" \
  -H "Content-Type: application/json" \
  -d '{"email":"user@example.com"}'

JavaScript

const res = await fetch('https://thefatbaby.com/api/v1/email/validate', {
  method: 'POST',
  headers: {
    Authorization: 'Bearer fb_live_YOUR_KEY',
    'Content-Type': 'application/json'
  },
  body: JSON.stringify({ email: 'user@example.com' })
});
console.log(await res.json());

Python

import requests
print(requests.post(
  'https://thefatbaby.com/api/v1/email/validate',
  headers={'Authorization': 'Bearer fb_live_YOUR_KEY'},
  json={'email': 'user@example.com'},
).json())

Request

{ "email": "user@example.com" }

Response

{
  "email": "user@example.com",
  "valid": true,
  "credits_used": 0
}

Pricing & credits

Single email validate is 0 credits; batch validate is 2 credits by default.

Common errors

  • 400Missing email
  • 402insufficient_credits (batch)

FAQ

Do you SMTP-probe mailboxes?

No. Validation is syntax/domain/disposable/role oriented and does not prove a mailbox exists.

Try without code

Use the matching online tool, then automate the same workflow with this API.