Layered validation
From string format through infrastructure (DNS/MX) to live SMTP signals when available.
Transparent classifications
Deliverable, undeliverable, risky, and unknown—aligned with what the verifier actually observed—not a fabricated 100% guarantee.
Catch-all detection context
Know when a domain likely accepts any local part so you segment or score those rows appropriately.
SMTP email check
Inspect SMTP responses and metadata alongside classification and score for support and QA.
Developer-friendly API
POST JSON, structured fields—integrate with forms, CRMs, and backends.
Self-hosted verifier deployment
Optional Docker deployment with environment controls (timeouts, sender identity, API key)—see docs in repo.