Advanced Email Validator


🚀 Advanced email validation library for Node.js with MX record checking, SMTP verification, disposable email detection, and much more. Now with batch processing, advanced caching, and detailed error reporting.

📋 Table of Contents

- Features
- Use Cases
- API / Cloud Service
- License
- Installation
- Quick Start
- API Reference
- Configuration
- Examples
- Performance & Caching
- Email Provider Databases
- Testing
- Contributing

Features

✅ Check email address validity

✅ Check email address domain validity in domain TLD list

✅ Check email address MX records

✅ Check email address SMTP connection

✅ Check email address disposable or burnable status

✅ Check email address free email provider status

✅ NEW: Batch email verification with concurrency control

✅ NEW: Detailed verification results with error codes

✅ NEW: Built-in caching for improved performance

✅ NEW: Automatic retry mechanism for transient failures

✅ NEW: RFC 5321 compliant validation

✅ NEW: Enhanced name detection from email addresses with composite name support

✅ NEW: Domain typo detection and suggestions with caching

✅ NEW: Get domain age via WHOIS lookup

✅ NEW: Get domain registration status via WHOIS lookup

✅ NEW: Serverless support for AWS Lambda, Vercel Edge, Cloudflare Workers, and more

Use Cases

- Increase delivery rate of email campaigns by removing spam emails
- Increase email open rate and your marketing IPs reputation
- Protect your website from spam, bots and fake emails
- Protect your product signup form from fake emails
- Protect your website forms from fake emails
- Protect your self from fraud orders and accounts using fake emails
- Integrate email address verification into your website forms
- Integrate email address verification into your backoffice administration and order processing

API / Cloud Hosted Service

We offer this email verification and validation and more advanced features in our Scalable Cloud API Service Offering - You could try it here Email Verification

---

License

email-validator-js is licensed under Business Source License 1.1.

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| Use Case | Is a commercial license required?|
|----------|-----------|
| Exploring email-validator-js for your own research, hobbies, and testing purposes | No |
| Using email-validator-js to build a proof-of-concept application | No |
| Using email-validator-js to build revenue-generating applications | Yes |
| Using email-validator-js to build software that is provided as a service (SaaS) | Yes |
| Forking email-validator-js for any production purposes | Yes |

📄 For commercial licensing, visit email-check.app/license/email-validator or contact us at sales@email-check.app.

---

Installation

Install the module through Yarn:
``bash
yarn add @devmehq/email-validator-js
`

Or NPM:
`bash
npm install @devmehq/email-validator-js
`

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- Node.js >= 12.0
- TypeScript >= 4.0 (for TypeScript users)

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- Uses Rollup for efficient bundling and tree-shaking
- Optimized build output with separate CJS and ESM modules
- Serverless builds for edge environments

Quick Start

`typescript
import { verifyEmail } from '@devmehq/email-validator-js';

// Basic usage
const result = await verifyEmail({
emailAddress: 'user@example.com',
verifyMx: true,
verifySmtp: true,
timeout: 3000
});

console.log(result.validFormat); // true
console.log(result.validMx); // true
console.log(result.validSmtp); // true or false
`

API Reference

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#### verifyEmail(params: IVerifyEmailParams): Promise

Basic email verification with backward compatibility.

Parameters:
- emailAddress (string, required): Email address to verify
- timeout (number): Timeout in milliseconds (default: 4000)
- verifyMx (boolean): Check MX records (default: false)
- verifySmtp (boolean): Verify SMTP connection (default: false)
- smtpPort (number): Custom SMTP port
- debug (boolean): Enable debug logging (default: false)
- detectName (boolean): Detect names from email address (default: false)
- nameDetectionMethod (function): Custom name detection method
- suggestDomain (boolean): Enable domain typo suggestions (default: false)
- domainSuggestionMethod (function): Custom domain suggestion method
- commonDomains (string[]): Custom list of domains for suggestions

Returns:
`typescript
{
validFormat: boolean;
validMx: boolean | null;
validSmtp: boolean | null;
detectedName?: DetectedName | null;
domainSuggestion?: DomainSuggestion | null;
}
`

#### verifyEmailDetailed(params: IVerifyEmailParams): Promise

Advanced verification with detailed results and error codes.

Additional Parameters:
- checkDisposable (boolean): Check for disposable emails (default: true)
- checkFree (boolean): Check for free email providers (default: true)
- retryAttempts (number): Retry attempts for failures (default: 1)
- detectName (boolean): Detect names from email address (default: false)
- suggestDomain (boolean): Enable domain typo suggestions (default: true in detailed mode)

Returns:
`typescript
{
valid: boolean;
email: string;
format: {
valid: boolean;
error?: VerificationErrorCode;
};
domain: {
valid: boolean | null;
mxRecords?: string[];
error?: VerificationErrorCode;
};
smtp: {
valid: boolean | null;
error?: VerificationErrorCode;
};
disposable: boolean;
freeProvider: boolean;
detectedName?: DetectedName | null;
domainSuggestion?: DomainSuggestion | null;
metadata?: {
verificationTime: number;
cached: boolean;
};
}
`

#### verifyEmailBatch(params: IBatchVerifyParams): Promise

Verify multiple emails in parallel with concurrency control.

Parameters:
- emailAddresses (string[], required): Array of emails to verify
- concurrency (number): Parallel processing limit (default: 5)
- detailed (boolean): Return detailed results (default: false)
- detectName (boolean): Detect names from email addresses
- suggestDomain (boolean): Enable domain typo suggestions
- Other parameters from verifyEmail

Returns:
`typescript
{
results: Map;
summary: {
total: number;
valid: number;
invalid: number;
errors: number;
processingTime: number;
};
}
`

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#### detectName(email: string): DetectedName | null
Detect first and last name from email address.

`typescript
const name = detectName('john.doe@example.com');
// Returns: { firstName: 'John', lastName: 'Doe', confidence: 0.9 }
`

Detection Patterns:
- Dot separator: john.doe → John Doe (90% confidence)
- Underscore: jane_smith → Jane Smith (80% confidence)
- Hyphen: mary-johnson → Mary Johnson (80% confidence)
- CamelCase: johnDoe → John Doe (70% confidence)
- Composite names: mo1.test2 → Mo1 Test2 (60% confidence)
- Mixed alphanumeric: user1.admin2 → User1 Admin2 (60% confidence)
- Smart number handling: john.doe123 → John Doe (80% confidence)
- Contextual suffixes: john.doe.dev → John Doe (70% confidence)
- Single name: alice → Alice (50% confidence)

Enhanced Features:
- Removes email aliases (text after +)
- Smart handling of numbers (preserves in composite names, removes trailing)
- Recognizes contextual suffixes (dev, company, sales, years)
- Handles complex multi-part names
- Proper name capitalization
- Filters out common non-name prefixes (admin, support, info, etc.)

#### detectNameFromEmail(params: IDetectNameParams): DetectedName | null
Advanced name detection with custom method support.

`typescript
const customMethod = (email: string) => {
// Your custom logic
return { firstName: 'Custom', lastName: 'Name', confidence: 1.0 };
};

const name = detectNameFromEmail({
email: 'user@example.com',
customMethod: customMethod
});
`

Parameters:
- email (string): Email address
- customMethod (function): Custom detection logic

#### defaultNameDetectionMethod(email: string): DetectedName | null
The default name detection implementation, exported for custom extensions.

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#### suggestEmailDomain(email: string, commonDomains?: string[]): DomainSuggestion | null
Detect and suggest corrections for misspelled email domains.

`typescript
const suggestion = suggestEmailDomain('user@gmial.com');
// Returns: { original: 'user@gmial.com', suggested: 'user@gmail.com', confidence: 0.95 }

// With custom domain list
const customDomains = ['company.com', 'enterprise.org'];
const customSuggestion = suggestEmailDomain('user@compny.com', customDomains);
`

Features:
- 70+ common email domains by default
- String similarity algorithm
- Known typo patterns (95% confidence)
- Smart thresholds based on domain length
- 24-hour caching for performance

#### suggestDomain(params: ISuggestDomainParams): DomainSuggestion | null
Advanced domain suggestion with custom method support.

`typescript
const suggestion = suggestDomain({
domain: 'gmial.com',
customMethod: myCustomMethod,
commonDomains: ['company.com']
});
`

Parameters:
- domain (string): Domain to check
- customMethod (function): Custom suggestion logic
- commonDomains (string[]): Custom domain list

#### defaultDomainSuggestionMethod(domain: string, commonDomains?: string[]): DomainSuggestion | null
The default domain suggestion implementation, exported for custom extensions.

#### isCommonDomain(domain: string, commonDomains?: string[]): boolean
Check if a domain is in the common domains list.

`typescript
isCommonDomain('gmail.com'); // true
isCommonDomain('mycompany.com'); // false

// With custom list
isCommonDomain('mycompany.com', ['mycompany.com']); // true
`

#### getDomainSimilarity(domain1: string, domain2: string): number
Calculate similarity score between two domains (0-1).

`typescript
getDomainSimilarity('gmail.com', 'gmial.com'); // 0.8
getDomainSimilarity('gmail.com', 'yahoo.com'); // 0.3
`

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> Note: WHOIS functions use PSL (Public Suffix List) validation to ensure domain validity before performing lookups. Invalid domains or domains without valid TLDs will return null.

#### getDomainAge(domain: string, timeout?: number): Promise
Get domain age information via WHOIS lookup.

`typescript
const ageInfo = await getDomainAge('example.com');
// Returns:
// {
// domain: 'example.com',
// creationDate: Date,
// ageInDays: 7890,
// ageInYears: 21.6,
// expirationDate: Date,
// updatedDate: Date
// }

// Works with email addresses and URLs too
await getDomainAge('user@example.com');
await getDomainAge('https://example.com/path');
`

Parameters:
- domain (string): Domain, email, or URL to check
- timeout (number): Timeout in milliseconds (default: 5000)

Returns: DomainAgeInfo object or null if lookup fails

#### getDomainRegistrationStatus(domain: string, timeout?: number): Promise
Get detailed domain registration status via WHOIS.

`typescript
const status = await getDomainRegistrationStatus('example.com');
// Returns:
// {
// domain: 'example.com',
// isRegistered: true,
// isAvailable: false,
// status: ['clientTransferProhibited'],
// registrar: 'Example Registrar',
// nameServers: ['ns1.example.com', 'ns2.example.com'],
// expirationDate: Date,
// isExpired: false,
// daysUntilExpiration: 365,
// isPendingDelete: false,
// isLocked: true
// }
`

Parameters:
- domain (string): Domain, email, or URL to check
- timeout (number): Timeout in milliseconds (default: 5000)

Returns: DomainRegistrationInfo object or null if lookup fails

Features:
- Supports 50+ TLDs with specific WHOIS servers
- Automatic WHOIS server discovery for unknown TLDs
- Parses various WHOIS response formats
- Uses PSL (Public Suffix List) for domain validation
- 1-hour result caching
- Extracts domain from emails and URLs

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#### isDisposableEmail(emailOrDomain: string): boolean
Check if email uses a disposable provider.

`typescript
isDisposableEmail('user@tempmail.com'); // true
isDisposableEmail('tempmail.com'); // true
isDisposableEmail('gmail.com'); // false
`

#### isFreeEmail(emailOrDomain: string): boolean
Check if email uses a free provider.

`typescript
isFreeEmail('user@gmail.com'); // true
isFreeEmail('yahoo.com'); // true
isFreeEmail('corporate.com'); // false
`

#### isValidEmail(emailAddress: string): boolean
Validate email format (RFC 5321 compliant).

`typescript
isValidEmail('user@example.com'); // true
isValidEmail('invalid.email'); // false
`

Validation Rules:
- Proper @ symbol placement
- Local part max 64 characters
- Domain max 253 characters
- No consecutive dots
- No leading/trailing dots
- Valid domain TLD

#### isValidEmailDomain(emailOrDomain: string): boolean
Validate if a domain has a valid TLD.

`typescript
isValidEmailDomain('example.com'); // true
isValidEmailDomain('example.invalid'); // false
`

#### clearAllCaches(): void
Clear all internal caches (including domain suggestions).

`typescript
clearAllCaches();
`

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#### DetectedName
`typescript
interface DetectedName {
firstName?: string;
lastName?: string;
confidence: number; // 0-1 scale
}
`

#### DomainSuggestion
`typescript
interface DomainSuggestion {
original: string;
suggested: string;
confidence: number; // 0-1 scale
}
`

#### NameDetectionMethod
`typescript
type NameDetectionMethod = (email: string) => DetectedName | null;
`

#### DomainSuggestionMethod
`typescript
type DomainSuggestionMethod = (domain: string) => DomainSuggestion | null;
`

#### DomainAgeInfo
`typescript
interface DomainAgeInfo {
domain: string;
creationDate: Date;
ageInDays: number;
ageInYears: number;
expirationDate: Date | null;
updatedDate: Date | null;
}
`

#### DomainRegistrationInfo
`typescript
interface DomainRegistrationInfo {
domain: string;
isRegistered: boolean;
isAvailable: boolean;
status: string[];
registrar: string | null;
nameServers: string[];
expirationDate: Date | null;
isExpired: boolean;
daysUntilExpiration: number | null;
isPendingDelete?: boolean;
isLocked?: boolean;
}
`

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#### COMMON_EMAIL_DOMAINS
Array of 70+ common email domains used for typo detection.

`typescript
import { COMMON_EMAIL_DOMAINS } from '@devmehq/email-validator-js';

console.log(COMMON_EMAIL_DOMAINS);
// ['gmail.com', 'yahoo.com', 'outlook.com', 'hotmail.com', ...]
`

Includes:
- Popular free providers (Gmail, Yahoo, Outlook, etc.)
- Business email services (Google Workspace, Microsoft, etc.)
- Privacy-focused providers (ProtonMail, Tutanota, etc.)
- Regional providers (GMX, Yandex, QQ, etc.)
- Hosting services (GoDaddy, Namecheap, etc.)

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`typescript
enum VerificationErrorCode {
INVALID_FORMAT = 'INVALID_FORMAT',
INVALID_DOMAIN = 'INVALID_DOMAIN',
NO_MX_RECORDS = 'NO_MX_RECORDS',
SMTP_CONNECTION_FAILED = 'SMTP_CONNECTION_FAILED',
SMTP_TIMEOUT = 'SMTP_TIMEOUT',
MAILBOX_NOT_FOUND = 'MAILBOX_NOT_FOUND',
MAILBOX_FULL = 'MAILBOX_FULL',
NETWORK_ERROR = 'NETWORK_ERROR',
DISPOSABLE_EMAIL = 'DISPOSABLE_EMAIL',
FREE_EMAIL_PROVIDER = 'FREE_EMAIL_PROVIDER'
}
`

Configuration Options

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Set a timeout in milliseconds for the smtp connection. Default: 4000.

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Enable or disable domain checking. This is done in two steps:
1. Verify that the domain does indeed exist
2. Verify that the domain has valid MX records

Default: false.

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Enable or disable mailbox checking. Only a few SMTP servers allow this, and even then whether it works depends on your IP's reputation with those servers. This library performs a best effort validation:
* It returns null for Yahoo addresses, for failed connections, for unknown SMTP errors
* It returns true for valid SMTP responses
* It returns false for SMTP errors specific to the address's formatting or mailbox existence

Default: false.

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Check if the email domain is a known disposable email provider. Default: false.

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Check if the email domain is a known free email provider. Default: false.

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Return detailed verification results with error codes. Default: false.

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Number of retry attempts for transient failures. Default: 1.

Examples

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`typescript
import { verifyEmail } from '@devmehq/email-validator-js';

const { validFormat, validSmtp, validMx } = await verifyEmail({
emailAddress: 'foo@email.com',
verifyMx: true,
verifySmtp: true,
timeout: 3000
});
// validFormat: true
// validMx: true
// validSmtp: true
`

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`typescript
import { verifyEmailDetailed } from '@devmehq/email-validator-js';

const result = await verifyEmailDetailed({
emailAddress: 'foo@email.com',
verifyMx: true,
verifySmtp: true,
checkDisposable: true,
checkFree: true
});
// result.valid: true
// result.disposable: false
// result.freeProvider: false
// result.domain.mxRecords: ['mx1.email.com', 'mx2.email.com']
// result.metadata.verificationTime: 125
`

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`typescript
import { verifyEmailBatch } from '@devmehq/email-validator-js';

const emails = ['user1@gmail.com', 'user2@example.com', 'invalid@fake.com'];

const result = await verifyEmailBatch({
emailAddresses: emails,
concurrency: 5,
verifyMx: true,
detailed: true
});
// result.summary.valid: 2
// result.summary.invalid: 1
// result.summary.processingTime: 234
`

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`typescript
import { detectName, verifyEmailDetailed } from '@devmehq/email-validator-js';

// Standalone name detection - now with composite name support
const name = detectName('john.doe@example.com');
// name: { firstName: 'John', lastName: 'Doe', confidence: 0.9 }

// Handle alphanumeric composite names
const composite = detectName('mo1.test2@example.com');
// composite: { firstName: 'Mo1', lastName: 'Test2', confidence: 0.6 }

// Smart handling of numbers and suffixes
const withNumbers = detectName('john.doe123@example.com');
// withNumbers: { firstName: 'John', lastName: 'Doe', confidence: 0.8 }

const withSuffix = detectName('jane.smith.dev@example.com');
// withSuffix: { firstName: 'Jane', lastName: 'Smith', confidence: 0.7 }

// Integrated with email verification
const result = await verifyEmailDetailed({
emailAddress: 'jane_smith@example.com',
detectName: true
});
// result.detectedName: { firstName: 'Jane', lastName: 'Smith', confidence: 0.8 }

// Custom detection method
const customMethod = (email: string) => {
// Your custom logic here
return { firstName: 'Custom', lastName: 'Name', confidence: 1.0 };
};

const resultCustom = await verifyEmail({
emailAddress: 'user@example.com',
detectName: true,
nameDetectionMethod: customMethod
});
`

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`typescript
import { suggestEmailDomain, verifyEmailDetailed } from '@devmehq/email-validator-js';

// Standalone domain suggestion
const suggestion = suggestEmailDomain('user@gmial.com');
// suggestion: { original: 'user@gmial.com', suggested: 'user@gmail.com', confidence: 0.95 }

// Integrated with email verification (enabled by default in detailed mode)
const result = await verifyEmailDetailed({
emailAddress: 'john@yaho.com',
suggestDomain: true // Default: true for detailed verification
});
// result.domainSuggestion: { original: 'john@yaho.com', suggested: 'john@yahoo.com', confidence: 0.9 }

// With custom domain list
const customDomains = ['company.com', 'enterprise.org'];
const resultCustom = await verifyEmail({
emailAddress: 'user@compny.com',
suggestDomain: true,
commonDomains: customDomains
});
// resultCustom.domainSuggestion: { suggested: 'user@company.com', confidence: 0.85 }
`

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When a domain does not exist or has no MX records:
`typescript
const result = await verifyEmail({
emailAddress: 'foo@bad-domain.com',
verifyMx: true,
verifySmtp: true
});
// validFormat: true
// validMx: false
// validSmtp: null (couldn't be performed)
`

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`typescript
const detailed = await verifyEmailDetailed({
emailAddress: 'user@suspicious-domain.com',
verifyMx: true,
verifySmtp: true,
checkDisposable: true,
checkFree: true
});

if (!detailed.valid) {
switch (detailed.domain.error) {
case VerificationErrorCode.DISPOSABLE_EMAIL:
console.log('Rejected: Disposable email');
break;
case VerificationErrorCode.NO_MX_RECORDS:
console.log('Rejected: Invalid domain');
break;
case VerificationErrorCode.MAILBOX_NOT_FOUND:
console.log('Rejected: Mailbox does not exist');
break;
}
}
`

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`typescript
const emails = [
'valid@gmail.com',
'test@tempmail.com',
'user@company.com',
// ... hundreds more
];

const batch = await verifyEmailBatch({
emailAddresses: emails,
concurrency: 10, // Process 10 emails simultaneously
verifyMx: true,
checkDisposable: true,
detailed: true
});

console.log(Processed ${batch.summary.total} emails);
console.log(Valid: ${batch.summary.valid});
console.log(Invalid: ${batch.summary.invalid});
console.log(Time: ${batch.summary.processingTime}ms);

// Filter out invalid emails
const validEmails = [];
for (const [email, result] of batch.results) {
if (result.valid) {
validEmails.push(email);
}
}
`

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`typescript
// First verification - hits DNS and SMTP
const first = await verifyEmail({
emailAddress: 'cached@example.com',
verifyMx: true
});
// Takes ~500ms

// Second verification - uses cache
const second = await verifyEmail({
emailAddress: 'cached@example.com',
verifyMx: true
});
// Takes ~1ms (cached)

// Clear cache if needed
clearAllCaches();
`

Note: Yahoo, Hotmail, and some providers always return validSmtp: true as they don't allow mailbox verification.

🌐 Serverless Deployment

The package includes serverless adapters for major cloud platforms. The serverless implementation provides email validation without Node.js dependencies, making it suitable for edge computing environments.

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`javascript
import { apiGatewayHandler } from '@devmehq/email-validator-js/serverless/aws';

export const handler = apiGatewayHandler;
`

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`javascript
import { edgeHandler } from '@devmehq/email-validator-js/serverless/vercel';

export const config = {
runtime: 'edge',
};

export default edgeHandler;
`

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`javascript
import { workerHandler } from '@devmehq/email-validator-js/serverless/cloudflare';

export default {
async fetch(request, env, ctx) {
return workerHandler(request, env, ctx);
},
};
`

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- ✅ Syntax validation
- ✅ Typo detection and domain suggestions
- ✅ Disposable email detection (full database)
- ✅ Free email provider detection (full database)
- ✅ Batch processing
- ✅ Built-in caching
- ❌ MX record validation (requires DNS)
- ❌ SMTP verification (requires TCP sockets)

For detailed serverless documentation and more platform examples, see docs/SERVERLESS.md.

📊 Performance & Caching

The library includes intelligent caching to improve performance:

| Cache Type | TTL | Description |
|------------|-----|-------------|
| MX Records | 1 hour | DNS MX record lookups |
| Disposable | 24 hours | Disposable email checks |
| Free Provider | 24 hours | Free email provider checks |
| Domain Valid | 24 hours | Domain validation results |
| SMTP | 30 minutes | SMTP verification results |
| Domain Suggestions | 24 hours | Domain typo suggestions |

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1. Use Batch Processing: For multiple emails, use verifyEmailBatch() for parallel processing
2. Enable Caching: Caching is automatic and reduces repeated lookups by ~90%
3. Adjust Timeouts: Lower timeouts for faster responses, higher for accuracy
4. Skip SMTP: If you only need format/MX validation, skip SMTP for 10x faster results
5. Domain Suggestions: Cached for 24 hours to avoid recalculating similarity scores
6. Name Detection: Lightweight operation with minimal performance impact

🗂️ Email Provider Databases

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View List - 5,000+ disposable email domains

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View List - 1,000+ free email providers

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Access the list of 70+ common email domains used for typo detection:

`typescript
import { COMMON_EMAIL_DOMAINS } from '@devmehq/email-validator-js';

console.log(COMMON_EMAIL_DOMAINS);
// ['gmail.com', 'yahoo.com', 'outlook.com', 'hotmail.com', ...]

// Use with your own domain validation
const isCommon = COMMON_EMAIL_DOMAINS.includes('gmail.com'); // true
`

Testing

Run the test suite:
`bash
yarn test
`

Run with coverage:
`bash
yarn test --coverage
`

Lint the code:
`bash
yarn lint
yarn lint-fix # Auto-fix issues
`

Build the project:
`bash
yarn build
`

Development

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`
email-validator-js/
├── src/ # Source code
│ ├── index.ts # Main entry point
│ ├── smtp.ts # SMTP verification
│ ├── dns.ts # DNS/MX lookups
│ ├── validator.ts # Format validation
│ ├── cache.ts # Caching system
│ ├── batch.ts # Batch processing
│ └── types.ts # TypeScript types
├── __tests__/ # Test files
├── examples/ # Usage examples
└── dist/ # Compiled output
`

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`bash
yarn build # Build TypeScript with Rollup
yarn test # Run tests with Jest
yarn lint # Run ESLint
yarn lint-fix # Fix ESLint issues
yarn typecheck # Run TypeScript type checking
`

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- Type Safety: Improved type inference reduces redundant type declarations
- Bundle Size: Optimized with tree-shaking and minification
- Performance: Faster builds with parallelized compilation
- Code Quality: Strict TypeScript mode with comprehensive type checking

Contributing

We welcome contributions! Please feel free to open an issue or create a pull request and fix bugs or add features. All contributions are welcome!

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

$3

`bash

Clone the repo

git clone https://github.com/devmehq/email-validator-js.git
cd email-validator-js

Install dependencies

yarn install

Run tests

yarn test

Build

yarn build
``

Support

For issues, questions, or commercial licensing:

🐛 Open an Issue
📧 Email Support
📄 Commercial License
🌐 Visit email-check.app

LICENSE

Business Source License 1.1 - see LICENSE file for details.

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The BSL allows use only for non-production purposes. Here's a comprehensive guide to help you understand when you need a commercial license:

| Use Case | Commercial License Required? | Details |
|----------|-----------|---------|
| Personal & Learning | | |
| 🔬 Exploring email-validator-js for research or learning | ✅ No | Use freely for educational purposes |
| 🎨 Personal hobby projects (non-commercial) | ✅ No | Build personal tools and experiments |
| 🧪 Testing and evaluation in development environment | ✅ No | Test all features before purchasing |
| Development & Prototyping | | |
| 💡 Building proof-of-concept applications | ✅ No | Create demos and prototypes |
| 🛠️ Internal tools (not customer-facing) | ✅ No | Use for internal development tools |
| 📚 Open source projects (non-commercial) | ✅ No | Contribute to the community |
| Commercial & Production Use | | |
| 💰 Revenue-generating applications | ❌ Yes | Any app that generates income |
| ☁️ Software as a Service (SaaS) products | ❌ Yes | Cloud-based service offerings |
| 📦 Distributed commercial software | ❌ Yes | Software sold to customers |
| 🏢 Enterprise production systems | ❌ Yes | Business-critical applications |
| 🔄 Forking for commercial purposes | ❌ Yes | Creating derivative commercial products |
| 🏭 Production use in any form | ❌ Yes | Live systems serving real users |
| Specific Scenarios | | |
| 🎓 Student projects and coursework | ✅ No | Academic use is encouraged |
| 🏗️ CI/CD pipelines (for commercial products) | ❌ Yes | Part of commercial development |
| 📧 Email validation in production APIs | ❌ Yes | Production service usage |
| 🛒 E-commerce checkout validation | ❌ Yes | Revenue-related validation |
| 📱 Mobile apps (free with ads or paid) | ❌ Yes | Monetized applications |

$3

Ask yourself these questions:
1. Will real users interact with this in production? → You need a license
2. Will this help generate revenue? → You need a license
3. Is this for learning or testing only? → No license needed
4. Is this an internal prototype or POC? → No license needed

$3

✨ Unlimited Usage - Use in all your production applications
🚀 Priority Support - Direct support from our engineering team
🔄 Regular Updates - Get the latest features and improvements
🛡️ Legal Protection - Full commercial rights and warranty
🏢 Enterprise Ready - Suitable for large-scale deployments

$3

Ready to use email-validator-js in production?

🛍️ Purchase a License - Simple pricing, instant activation
📧 Contact Sales - For enterprise or custom needs