Most email verification tools are black boxes. They tell you an email is "valid" or "risky" — but never explain why. You're forced to trust proprietary logic you can't inspect, audit, or control.

Verifio changes that.

We believe email verification should be:

• 🔍 Transparent — see the exact signals behind every verification result
• 🔓 Open source — audit the logic, contribute improvements, own your infrastructure
• 🧩 Self-hostable — deploy on your own servers, no vendor lock-in
• ⚡ Developer-first — built as infrastructure, not just another SaaS dashboard

✅ Multi-signal verification — syntax, DNS, MX records, SMTP handshake, catch-all detection
✅ Explainable results — every response includes raw verification signals
✅ Zero vendor lock-in — same engine for hosted API and self-hosted deployments
✅ Production-ready — rate limiting, bulk verification, webhook support
✅ Privacy-focused — self-host for complete data control
✅ MIT licensed — use commercially without restrictions

npm install @verifio/sdk

import { verifyEmail } from "@verifio/sdk";

const result = await verifyEmail("user@example.com");

console.log(result);

Response:

{
  "status": "valid",
  "confidence": 0.92,
  "signals": {
    "syntax": true,
    "dns": true,
    "mx": true,
    "smtp": "accepted",
    "disposable": false,
    "catchAll": false,
    "roleAccount": false
  },
  "risk": "low",
  "provider": "gmail"
}

👉 Get your free API key

Deploy Verifio on your own infrastructure in under 2 minutes:

docker run -p 3000:3000 \
  -e SMTP_TIMEOUT=5000 \
  -e RATE_LIMIT=100 \
  verifio/verifio

Test the API:

curl http://localhost:3000/verify?email=user@example.com

For production deployments with Docker Compose, Kubernetes, or custom configurations, see the Self-Hosting Guide.

Verifio combines multiple verification layers to determine email validity:

Every result includes raw signals from each layer — no hidden logic.

Verifio is built for real-world products and data pipelines:

• ✉️ User onboarding — validate emails during signup to reduce fake accounts
• 📊 Lead capture forms — ensure high-quality contact data from day one
• 🔄 CRM & marketing automation — clean lists before campaigns to improve deliverability
• 🛒 E-commerce & marketplaces — prevent fraud and improve user trust
• 🧹 Bulk email list cleaning — verify thousands of emails efficiently
• 🔗 Data enrichment pipelines — integrate verification into ETL workflows

If email quality affects deliverability, trust, or revenue — Verifio fits.

Both options use the same verification engine — same logic, same results.

We welcome contributions from the community! Here's how you can help:

• 🐛 Report bugs
• 💡 Request features
• 🔧 Submit pull requests
• 📖 Improve documentation
• ⭐ Star the repo to show support

Check out our Contributing Guide to get started.

• Bulk verification API endpoint
• Webhook support for async verification
• Email reputation scoring
• Integration with popular CRM platforms
• Advanced catch-all detection with AI
• Multi-language SDK support (Python, Go, Ruby)

See the full roadmap and vote on features.

Verifio is licensed under the MIT License. You're free to use, modify, and distribute it — even commercially.

• 🌐 Website: verifio.email
• 📘 Documentation: verifio.email/docs
• ⭐ GitHub: github.com/verifio-email/verifio
• 💬 Community: Discord • Twitter