int2words

Convert integers into words.

Features and limitations:

• Languages: English and Japanese.
• Integer range: 0 → 2⁵³–1.
  • While 64-bit floating-point numbers technically support numbers up to approximately 1.8 × 10³⁰⁸, there is a significant loss of precision. 2⁵³–1 is the largest integer with no loss of precision.

View example.

Install

npm install int2words

Usage

import { int2en, int2ja } from 'int2words';

console.log(int2en(321)); // "three hundred twenty-one"
console.log(int2ja(321)); // "三百二十一"
console.log(int2en(-1)); // Invalid input: ""

/**
 * Optionally throw an error.
 */
try {
  int2en(-1, { throwError: true });
} catch (error) {
  if (error instanceof CoercionError) {
    console.error(error); // "CoercionError: Expected a positive integer."
  }
  throw error;
}

const { int2en, int2jw } = require('int2words');

No-Bundler Install and Usage

To use in browsers directly and without bundlers.

• Save int2words.min.js to your project and add <script src="PATH/TO/int2words.min.js"> in your HTML file.
• Or add <script src="https://unpkg.com/int2words@2.0.1/dist/legacy-iife/int2words.min.js"> in your HTML file.

The library is now available globally through the int2words object.

console.log(int2words.int2en(321)); // "three hundred twenty-one"

Changelog

v2.0.1 (2025-3-28)

Update README, deps, etc.

v2.0.0 (2025-3-14)

Change name and modernize.

v1.2.7 (2016-5-4)

Acknowledgments

• Originally a modification from http://stackoverflow.com/questions/14766951/convert-digits-into-words-with-javascript.

License

This project is licensed under the GNU General Public License (GPL).