rupee-india

🇮🇳 A lightweight, zero-dependency Indian Rupee formatter for Node.js

Format numbers using the Indian numbering system (thousand, lakh, crore), convert amounts to words, and display with the ₹ symbol — all without any external dependencies.

✨ Features

• 🔢 Indian comma grouping — formats numbers as 1,00,000 instead of 100,000
• 💰 Rupee symbol — prefix with ₹ in one call
• 🗣️ Number to words — "One Lakh Rupees" with paise support
• 📊 Lakh / Crore helpers — express values in lakh or crore units
• ⚡ Zero dependencies — lightweight and fast
• 🛡️ Input validation — descriptive errors for invalid input
• 🧩 CommonJS — works with require() out of the box (Node.js 16+)

Installation

npm install rupee-india

Quick Start

const rupee = require("rupee-india");

rupee.format(1000000);           // "10,00,000"
rupee.formatWithSymbol(50000);   // "₹50,000"
rupee.toWords(1250);             // "One Thousand Two Hundred Fifty Rupees"
rupee.lakhs(1000000);            // "10 Lakh"
rupee.crores(10000000);          // "1 Crore"

API Reference

format(number)

Converts a number to a string with Indian comma grouping (groups of 3 then 2 from the right).

| Parameter | Type | Description | |-----------|------|-------------| | number | number \| string | The number to format |

Returns: string — comma-formatted number.

rupee.format(1000);        // "1,000"
rupee.format(100000);      // "1,00,000"
rupee.format(10000000);    // "1,00,00,000"
rupee.format(1234567890);  // "1,23,45,67,890"
rupee.format(-50000);      // "-50,000"
rupee.format(1234.56);     // "1,234.56"
rupee.format("100000");    // "1,00,000"  (string input)

formatWithSymbol(number)

Same as format() but prefixed with the ₹ Rupee symbol.

| Parameter | Type | Description | |-----------|------|-------------| | number | number \| string | The number to format |

Returns: string — formatted number with ₹ prefix.

rupee.formatWithSymbol(100000);   // "₹1,00,000"
rupee.formatWithSymbol(0);        // "₹0"
rupee.formatWithSymbol(-500);     // "-₹500"
rupee.formatWithSymbol(10000000); // "₹1,00,00,000"

toWords(number)

Converts a number to Indian-English currency words. Supports paise (up to 2 decimal places) and negative numbers.

| Parameter | Type | Description | |-----------|------|-------------| | number | number \| string | The number to convert |

Returns: string — human-readable currency string.

rupee.toWords(0);          // "Zero Rupees"
rupee.toWords(1500);       // "One Thousand Five Hundred Rupees"
rupee.toWords(100000);     // "One Lakh Rupees"
rupee.toWords(10000000);   // "One Crore Rupees"
rupee.toWords(1234567);    // "Twelve Lakh Thirty Four Thousand Five Hundred Sixty Seven Rupees"
rupee.toWords(21.50);      // "Twenty One Rupees and Fifty Paise"
rupee.toWords(-500);       // "Minus Five Hundred Rupees"

lakhs(number)

Express a number in Lakh units (1 Lakh = 1,00,000).

| Parameter | Type | Description | |-----------|------|-------------| | number | number \| string | The number to convert |

Returns: string — value in lakhs with label.

rupee.lakhs(100000);   // "1 Lakh"
rupee.lakhs(1000000);  // "10 Lakh"
rupee.lakhs(250000);   // "2.5 Lakh"
rupee.lakhs(50000);    // "0.5 Lakh"

crores(number)

Express a number in Crore units (1 Crore = 1,00,00,000).

| Parameter | Type | Description | |-----------|------|-------------| | number | number \| string | The number to convert |

Returns: string — value in crores with label.

rupee.crores(10000000);   // "1 Crore"
rupee.crores(100000000);  // "10 Crore"
rupee.crores(75000000);   // "7.5 Crore"

Error Handling

All functions validate their input and throw descriptive errors:

rupee.format("abc");       // TypeError: Expected a number ...
rupee.format(Infinity);    // RangeError: Number must be finite ...
rupee.format(null);        // TypeError: Expected a number ...
rupee.format(undefined);   // TypeError: Expected a number ...

Running Tests

npm test

Project Structure

rupee-india/
├── package.json
├── README.md
├── LICENSE
├── index.js          # Main entry point — re-exports all functions
├── src/
│   ├── format.js     # format, formatWithSymbol, lakhs, crores
│   ├── words.js      # toWords (number → Indian-English currency words)
│   └── helpers.js    # Input validation & shared utilities
└── test/
    └── test.js       # Comprehensive test suite

Contributing

Contributions are welcome! Feel free to open an issue or submit a pull request on the GitHub repository.

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

Author

Dheeraj Singh — GitHub

License

MIT © 2026 Dheeraj Singh