A comprehensive email validation system that combines RFC compliance, multi-layer validation, and advanced heuristics to provide the most accurate email validation in the world.

• RFC 5321/5322 Compliant: Full implementation of email standards
• Multi-Layer Validation: Syntax → Domain → MX → SMTP → Heuristics
• International Support: IDN (Internationalized Domain Name) support
• Real SMTP Testing: Actual mailbox existence verification
• Comprehensive Database: 4,725+ disposable email domains from GitHub

1. Syntax Layer: RFC-compliant email parsing with quoted strings and comments
2. Domain Layer: DNS resolution and MX record verification
3. Mail Server Layer: Real SMTP handshake and mailbox verification
4. Deliverability Layer: Disposable detection, role-based filtering, typo correction
5. Reputation Layer: Domain health, SPF/DMARC/DKIM checking

• Gmail Normalization: Handles dots and plus aliases correctly
• Role-Based Detection: Identifies admin@, support@, info@ addresses
• Catch-All Detection: Detects domains that accept all emails
• Typo Correction: Intelligent suggestions for common typos
• Bulk Validation: Process hundreds of emails simultaneously
• Real-Time Scoring: 0-100 confidence score with detailed factors

┌─────────────────┐    ┌─────────────────┐    ┌─────────────────┐
│   Frontend      │    │   Backend       │    │   External      │
│   (React + Vite) │◄──►│   (Node.js)     │◄──►│   Services      │
│                 │    │                 │    │                 │
│ • Single Email  │    │ • Email Validator│    │ • DNS Lookups   │
│ • Bulk Email    │    │ • SMTP Testing   │    │ • SMTP Servers  │
│ • Results UI    │    │ • Domain Health  │    │ • Blocklists    │
└─────────────────┘    └─────────────────┘    └─────────────────┘

The validator now includes a Strict Mode that enables maximum validation strictness with a single switch. When enabled:

• Stricter RFC Compliance: Enforces stricter email format rules
• Enhanced SMTP Testing: More thorough mailbox verification
• Deep Domain Analysis: Comprehensive domain reputation checks
• Advanced Heuristics: Sophisticated pattern detection
• Role-Based Detection: Identifies role-based accounts (admin@, support@)
• Gmail Normalization: Proper handling of Gmail dots and plus aliases
• Catch-All Detection: Identifies domains that accept all emails
• Stricter Scoring: Higher thresholds for validity (85+ instead of 75+)

// Frontend - Toggle strict mode with UI switch
// Backend - Automatically enabled when useStrictMode: true
const options = {
  useStrictMode: true  // Enables all strict features
};

• Node.js >= 18.0.0
• npm or yarn

1. Clone the repository

   git clone <repository-url>
   cd vivid-valid

2. Install Backend Dependencies

   cd backend
   npm install

3. Install Frontend Dependencies

   cd ..
   npm install

4. Start the Backend Server

   cd backend
   npm start

   Backend will run on http://localhost:3001

5. Start the Frontend Development Server

   cd ..
   npm run dev

   Frontend will run on http://localhost:5173

Create a .env file in the backend directory:

PORT=3001
NODE_ENV=development
SMTP_TIMEOUT=5000
SMTP_FROM_DOMAIN=validator.example.com
ENABLE_CACHE=true
CACHE_TTL=300

Update the API base URL in src/lib/emailValidation.ts:

const API_BASE_URL = "http://localhost:3001/api";

const response = await fetch("http://localhost:3001/api/email/validate", {
  method: "POST",
  headers: { "Content-Type": "application/json" },
  body: JSON.stringify({ email: "john@gmail.com" }),
});

const result = await response.json();
console.log(result);

const response = await fetch("http://localhost:3001/api/email/validate-bulk", {
  method: "POST",
  headers: { "Content-Type": "application/json" },
  body: JSON.stringify({
    emails: ["john@gmail.com", "jane@yahoo.com", "invalid-email"],
  }),
});

const result = await response.json();
console.log(result);

{
  "success": true,
  "data": {
    "input": "john@gmail.com",
    "syntax_valid": true,
    "domain_valid": true,
    "mx_found": true,
    "smtp_deliverable": false,
    "disposable": false,
    "typo_detected": false,
    "suggestion": null,
    "score": 82,
    "status": "valid",
    "reason": "Email appears to be valid and deliverable",
    "factors": {
      "format": true,
      "domain": true,
      "mx": true,
      "smtp": false,
      "reputation": 75,
      "deliverability": 100
    },
    "domainHealth": {
      "spf": true,
      "dkim": false,
      "dmarc": true,
      "blacklisted": false,
      "reputation": 100
    },
    "validation_time": 259,
    "checks_performed": [
      "syntax",
      "typos",
      "disposable",
      "domain",
      "mx",
      "smtp",
      "domain_health"
    ]
  }
}

cd backend
npm test

npm test

Use the provided test-emails.txt file for comprehensive testing:

curl -X POST http://localhost:3001/api/email/validate-bulk \
  -H "Content-Type: application/json" \
  -d "{\"emails\": $(cat test-emails.txt | jq -R -s -c 'split("\n")[:-1]')}"

• Validation Speed: ~2-5 seconds per email (with SMTP testing)
• Bulk Processing: 100+ emails in parallel
• Memory Usage: Optimized with caching and connection pooling
• Rate Limiting: Built-in protection against abuse

• Input Validation: All inputs sanitized and validated
• Rate Limiting: Prevents abuse and DoS attacks
• CORS: Configured for secure cross-origin requests
• Helmet: Security headers for Express.js
• No External APIs: All validation happens locally

1. Fork the repository
2. Create a feature branch (git checkout -b feature/amazing-feature)
3. Commit your changes (git commit -m 'Add some amazing feature')
4. Push to the branch (git push origin feature/amazing-feature)
5. Open a Pull Request

This project is licensed under the MIT License - see the LICENSE file for details.

• Disposable Email Domains: disposable-email-domains for the comprehensive blocklist
• RFC Standards: Internet Engineering Task Force for email specifications
• Node.js Ecosystem: All the amazing packages that make this possible

For support, please open an issue in the GitHub repository or contact the development team.

Built with ❤️ for the most accurate email validation in the world