Hermes

Email validation
that just works

Verify syntax, MX records, and live SMTP delivery in a single API call. Stop bounces before they damage your sender reputation.

Bounced emails don't just hurt delivery rates. They damage sender reputation, waste engineering time, and erode trust with your users. Hermes catches invalid addresses before they ever touch your mail server.

REST API

One call. Full confidence.

A single POST returns syntax, MX, SMTP, disposable, and catch-all results — plus a confidence score from 0 to 1.

API live
<200ms avg
View docs
POST /api/v1/validate
curl -X POST \
  http://localhost:3000/v1/validate \
  -H "Authorization: Bearer hms_••••••••" \
  -H "Content-Type: application/json" \
  -d '{
    "email": "user@example.com",
    "checkSmtp": true
  }'
{
  "email": "user@example.com",
  "valid": true,
  "score": 0.95,
  "checks": {
    "syntax":     true,
    "mx":         true,
    "smtp":       true,
    "disposable": false,
    "catchAll":   false
  }
}

Everything your app needs

Comprehensive checks, millisecond response times, and a dead-simple API your team can integrate in minutes.

SMTP Verification

Connect directly to mail servers and confirm real mailbox existence without sending a single email.

Disposable Detection

Automatically block throwaway addresses from tempmail, mailinator, and hundreds of known providers.

Batch Processing

Validate up to 100 addresses in one request. Clean your lists and protect sender reputation at scale.

Simple, transparent pricing

Start free. Upgrade as you grow.

Free

$0/month

Perfect for testing and small projects.

  • 100 validations / month
  • Syntax & MX checks
  • Disposable detection
  • 1 API key
Start for free
Most popular

Starter

$9/month

For apps that need reliable email verification.

  • 10,000 validations / month
  • Full SMTP verification
  • Priority support
  • 3 API keys
Subscribe

Pro

$49/month

For high-volume production workloads.

  • 100,000 validations / month
  • Batch API (up to 100 emails)
  • Catch-all detection
  • Dedicated support
Subscribe

Start validating
in minutes

100 free validations monthly. No credit card needed.

Create free account