mikkelscheike
Email Provider Links
🔒 Modern email provider detection library with enhanced TypeScript support and enterprise security
A robust TypeScript library providing direct links to 93 email providers (180 domains) with concurrent DNS resolution, optimized performance, comprehensive email validation, and advanced security features for login and password reset flows.
🚀 Try it out
Live Demo - Test the library with any email address and see it in action!
✨ New in Version 2.7.0
- 🚀 Modern TypeScript: Updated to latest TypeScript 2025 standards with strict type checking
- 🌍 Enhanced International Support: Improved IDN validation and Punycode handling
- 📧 Advanced Email Validation: Comprehensive validation with detailed error reporting
- 🔄 Batch Processing: Efficiently process multiple emails with deduplication
- 🛡️ Improved Security: Enhanced cryptographic integrity verification
- ⚡ Better Performance: Optimized concurrent DNS with smart caching
- 🎯 Developer Experience: Enhanced error messages and debugging information
- 📊 Development Mode: Memory usage tracking when NODE_ENV=development
✨ Core Features
- 🚀 Fast & Lightweight: Zero dependencies, ultra-low memory (~0.08MB initial, ~0.03MB per 1000 ops)
- 📧 93 Email Providers: Gmail, Outlook, Yahoo, ProtonMail, iCloud, and many more
- 🌐 207 Domains Supported: Comprehensive international coverage
- 🌍 Full IDN Support: International domain names with RFC compliance and Punycode
- ✅ Advanced Email Validation: International email validation with detailed error reporting
- 🏢 Business Domain Detection: DNS-based detection for custom domains (Google Workspace, Microsoft 365, etc.)
- 🔒 Enterprise Security: Multi-layer protection against malicious URLs and supply chain attacks
- 🛡️ URL Validation: HTTPS-only enforcement with domain allowlisting
- 🔐 Integrity Verification: Cryptographic hash verification for data integrity
- 📝 Type Safe: Full TypeScript support with comprehensive interfaces
- ⚡ Performance Optimized: Smart DNS fallback with configurable timeouts
- 🚦 Rate Limiting: Built-in DNS query rate limiting to prevent abuse
- 🔄 Email Alias Detection: Normalize Gmail dots, plus addressing, and provider-specific aliases
- 🛡️ Fraud Prevention: Detect duplicate accounts through email alias manipulation
- 📦 Batch Processing: Efficiently process multiple emails with deduplication
- 🧪 Thoroughly Tested: 424 tests with 93.16% code coverage
Installation
Using npm:
npm install @mikkelscheike/email-provider-linksRequirements
- Node.js:
>=18.0.0(Tested on 18.x, 20.x, 22.x, 24.x) - TypeScript:
>=4.0.0(optional, but recommended) - Zero runtime dependencies - No external packages required
Node.js 24 Support ✨
Fully compatible with the latest Node.js 24.x! The library is tested on:
- Node.js 18.x (LTS)
- Node.js 20.x (LTS)
- Node.js 22.x (Current)
- Node.js 24.x (Latest) - Full support with latest features
Supported Providers
📊 Current Coverage: 93 providers supporting 207 domains
Consumer Email Providers:
- Gmail (2 domains): gmail.com, googlemail.com
- Microsoft Outlook (15 domains): outlook.com, hotmail.com, live.com, msn.com, and 11 more
- Yahoo Mail (19 domains): yahoo.com, yahoo.co.uk, yahoo.fr, ymail.com, rocketmail.com, and 14 more
- ProtonMail (4 domains): proton.me, protonmail.com, protonmail.ch, pm.me
- iCloud Mail (3 domains): icloud.com, me.com, mac.com
- Tutanota (6 domains): tutanota.com, tutanota.de, tutamail.com, tuta.io, keemail.me, tuta.com
- SimpleLogin (10 domains): simplelogin.io, 8alias.com, aleeas.com, slmail.me, and 6 more
- FastMail, Zoho Mail, AOL Mail, GMX, Web.de, Mail.ru, QQ Mail, NetEase, Yandex, and many more
Business Email (via DNS detection):
- Microsoft 365 (Business domains via MX/TXT records)
- Google Workspace (Custom domains via DNS patterns)
- Amazon WorkMail (AWS email infrastructure via awsapps.com patterns)
- Zoho Workplace, FastMail Business, GoDaddy Email, Bluehost Email
- ProtonMail Business, Rackspace Email, IONOS, and others
Security & Privacy Focused:
- ProtonMail, Tutanota, Hushmail, CounterMail, Posteo
- Mailfence, SimpleLogin, AnonAddy
International Providers:
- Europe: GMX, Web.de, Orange, Free.fr, T-Online, Libero, Virgilio, Telekom, Tiscali, Skynet, Telenet, Xs4All, Planet.nl, Bluewin, Eircom
- Asia: QQ Mail, NetEase, Sina Mail, Alibaba Mail, Rakuten, Nifty, Naver (Korea), Daum (Korea), Biglobe (Japan), Sify, IndiatTimes (India)
- Eastern Europe: Centrum (Czech/Slovak), Interia, Onet (Poland), Rambler (Russia)
- Other Regions: UOL, Terra (Brazil), Telkom (South Africa), Xtra (New Zealand)
API Reference
getEmailProvider(email, timeout?)
Recommended - Detects any email provider including business domains.
// 🚀 SAME CALL, DIFFERENT SCENARIOS:
// ✅ For known providers (Gmail, Yahoo, etc.) - INSTANT response
const gmail1 = await getEmailProvider('user@gmail.com'); // No timeout needed
const gmail2 = await getEmailProvider('user@gmail.com', 3000); // Same speed - timeout ignored
// Both return instantly: { provider: "Gmail", loginUrl: "https://mail.google.com/mail/" }
// 🔍 For business domains - DNS lookup required, timeout matters
const biz1 = await getEmailProvider('user@mycompany.com'); // 5000ms timeout (default)
const biz2 = await getEmailProvider('user@mycompany.com', 2000); // 2000ms timeout (faster fail)
const biz3 = await getEmailProvider('user@mycompany.com', 10000); // 10000ms timeout (slower networks)
// All may detect: { provider: "Google Workspace", detectionMethod: "mx_record" }
// 🎯 WHY USE CUSTOM TIMEOUT?
// - Faster apps: Use 2000ms to fail fast on unknown domains
// - Slower networks: Use 10000ms to avoid premature timeouts
// - Enterprise: Use 1000ms for strict SLA requirementsgetEmailProviderSync(email)
Synchronous - Only checks predefined domains (no DNS lookup).
const result = getEmailProviderSync('user@gmail.com');
// Returns: { provider, loginUrl, email }getEmailProviderFast(email, options?)
High-performance - Concurrent DNS with detailed timing information.
const result = await getEmailProviderFast('user@mycompany.com', {
enableParallel: true,
collectDebugInfo: true,
timeout: 3000
});
console.log(result.timing); // { mx: 120, txt: 95, total: 125 }
console.log(result.confidence); // 0.9Real-World Example
async function handlePasswordReset(email: string) {
// Validate email first
const validation = validateEmailAddress(email);
if (!validation.isValid) {
throw new Error(`Invalid email: ${validation.error?.message}`);
}
// Get provider information
const result = await getEmailProvider(validation.normalizedEmail);
return {
providerUrl: result.loginUrl,
providerName: result.provider?.companyProvider || null,
isSupported: result.provider !== null,
detectionMethod: result.detectionMethod
};
}Configuration
// Custom DNS timeout (default: 5000ms)
const result = await getEmailProvider(email, 2000);
// Rate limiting configuration
import { Config } from '@mikkelscheike/email-provider-links';
console.log('Max requests:', Config.MAX_DNS_REQUESTS_PER_MINUTE); // 10
console.log('Default timeout:', Config.DEFAULT_DNS_TIMEOUT); // 5000msAdvanced Usage
<summary>📚 Advanced Features & Specialized Use Cases</summary>
Library Statistics
import { getLibraryStats, getSupportedProviders } from '@mikkelscheike/email-provider-links';
const stats = getLibraryStats();
console.log(`Version ${stats.version} supports ${stats.providerCount} providers`);
const providers = getSupportedProviders();
console.log(`Total providers: ${providers.length}`);Email Alias Detection & Normalization
import {
normalizeEmail,
emailsMatch
} from '@mikkelscheike/email-provider-links';
// Prevent duplicate accounts
async function registerUser(email: string) {
const canonical = normalizeEmail(email);
const existingUser = await findUserByEmail(canonical);
if (existingUser) {
throw new Error('Email already registered');
}
await createUser({ email: canonical });
}
// Check if login email matches registration
const match = emailsMatch('user@gmail.com', 'u.s.e.r+work@gmail.com');
console.log(match); // true - same person
// Simple normalization
const canonical = normalizeEmail('u.s.e.r+work@gmail.com');
console.log(canonical); // 'user@gmail.com'Provider Support Checking
import { isEmailProviderSupported, extractDomain } from '@mikkelscheike/email-provider-links';
// Check if provider is supported
const supported = isEmailProviderSupported('user@gmail.com');
// Extract domain safely
const domain = extractDomain('USER@EXAMPLE.COM');
console.log(domain); // 'example.com'Performance and Detection System
For detailed performance metrics and information about the detection system, refer to Performance and Detection System.
Development Mode Features
When NODE_ENV is set to 'development', the library provides additional insights:
// Memory usage is automatically logged:
// 🚀 Current memory usage: 0.08 MBMemory Management
The library implements careful memory management:
- Initial load: ~0.08MB heap usage
- Batch operations: ~0.03MB per 1000 operations
- Maximum load: < 25MB even under heavy concurrent operations
- Automatic garbage collection hints
- Memory usage logging in development mode
Performance Benchmarks
This package is designed to be extremely memory efficient and fast:
- Provider loading: ~0.08MB heap usage, ~0.5ms
- Email lookups: ~0.03MB heap usage per 100 operations
- Concurrent DNS: ~0.03MB heap usage, ~27ms for 10 lookups
- Large scale (1000 ops): ~0.03MB heap usage, ~1.1ms total
- International validation: <1ms for complex IDN domains
To run benchmarks locally:
npm run benchmarkContributing
We welcome contributions! See CONTRIBUTING.md for guidelines on adding new email providers.
Quality Assurance: This project maintains high standards with 424 comprehensive tests achieving 93.16% code coverage (96.46% function coverage). Security Note: All new providers undergo security validation and must pass our allowlist verification.
Security
For security concerns or to report vulnerabilities, see our Security Policy.
License
MIT License - see LICENSE file for details.
Zero dependencies • TypeScript-first • Production ready • International support