mask-email

A simple, lightweight utility to mask email addresses for privacy. Zero dependencies.

Installation

npm install mask-email

Usage

const maskEmail = require('mask-email');

// Basic usage
maskEmail('[email protected]');        // 'j******@gmail.com'
maskEmail('[email protected]');          // 'j***@example.org'

// Custom masking character
maskEmail('[email protected]', { maskChar: '#' });  // 'u###@domain.com'

// Show more characters at start
maskEmail('[email protected]', { unmaskedStart: 3 });  // 'joh****@gmail.com'

// Show characters at end of username
maskEmail('[email protected]', { 
  unmaskedStart: 2, 
  unmaskedEnd: 2 
});  // 'jo***[email protected]'

// Mask domain too
maskEmail('[email protected]', { maskDomain: true });  // 'u***@g******.com'

API

maskEmail(email, options?)

Parameters

• email (string): The email address to mask
• options (object, optional): Masking configuration
  • maskChar (string): Character to use for masking (default: '*')
  • unmaskedStart (number): Number of characters to show at start of username (default: 1)
  • unmaskedEnd (number): Number of characters to show at end of username (default: 0)
  • maskDomain (boolean): Whether to mask the domain name (default: false)

Returns

• (string): The masked email address

Throws

• Error: If email is not a string or has invalid format

Examples

// Different masking styles
maskEmail('[email protected]');                               // 'h****@world.com'
maskEmail('[email protected]');                                        // '[email protected]' (too short to mask much)
maskEmail('[email protected]', { unmaskedStart: 4 }); // 'very*********@company.com'

// Custom characters
maskEmail('[email protected]', { maskChar: '•' });           // 't•••@example.com'
maskEmail('[email protected]', { maskChar: 'X' });           // '[email protected]'

// Privacy modes
maskEmail('[email protected]', { 
  maskDomain: true,
  maskChar: '#' 
});  // 's########@p######.org'

License

MIT

Contributing

Pull requests welcome! Please ensure tests pass.

Running Tests

npm test

Development

To contribute to this project:

1. Fork the repository
2. Create a feature branch
3. Make your changes
4. Add tests for new functionality
5. Ensure all tests pass
6. Submit a pull request

Test File Structure

The project includes comprehensive tests in test.js. You can run them with:

// Example test structure
const maskEmail = require('./index.js');

test('Basic email masking', () => {
  assertEqual(maskEmail('[email protected]'), 'j***@example.com');
});