Email Validator API — Syntax, MX & SMTP Verification

Validate email addresses without paying per-email fees to an external service. This Actor runs as a REST API and checks each address locally:

• Syntax — RFC-5322-style local validation
• MX lookup — does the domain actually receive mail?
• Disposable detection — mailinator, tempmail, yopmail, …
• Role address detection — admin@, support@, noreply@, …
• SMTP handshake (optional) — real RCPT TO probe; never sends an email
• Verdict + score — valid / risky / invalid and 0.0–1.0 confidence

Why this Actor

Commercial email-verification APIs charge $0.002–$0.01 per email. This Actor does the same checks inside the run — you pay only the Actor usage.

Endpoints

Method	Path	Description
POST	/validate	Validate up to 20 addresses: {"emails": [...], "smtpCheck": true}
GET	/validate?email=...	Validate a single address
GET	/health	Liveness probe

curl -X POST "https://<container-url>/validate" \
  -H "Content-Type: application/json" \
  -d '{"emails": ["galih.rakasiwi@gmail.com", "bad@mailinator.com", "not-an-email"]}'

Output

{
  "count": 3,
  "results": [
    {
      "email": "galih.rakasiwi@gmail.com",
      "verdict": "valid",
      "syntaxValid": true,
      "domainValid": true,
      "mxFound": true,
      "mxRecords": ["gmail-smtp-in.l.google.com"],
      "smtpAccepts": true,
      "disposable": false,
      "roleAddress": false,
      "score": 1.0,
      "checks": ["syntax:ok", "mx:ok", "smtp:True"]
    }
  ]
}

Notes

• SMTP port 25 is blocked in many datacenter networks; when it is unreachable the result is smtpAccepts: null (unknown) — syntax + MX verdicts still work.
• Batch is capped at 20 addresses per request, with a hard overall timeout.
• Set smtpCheck: false for fast bulk validation.

Local development

pip install -r requirements.txt
uvicorn src.main:app --reload

Related searches

email verification api, email validator, bulk email checker, email list cleaning, mx lookup, smtp verification, disposable email detection