Invoice Amount in Words

Most invoicing regulations globally require the total to be written in words. to-words handles 132 locales — generate the right phrase for every customer's jurisdiction.

The Problem

Invoice systems often store amounts correctly but render them poorly for print, compliance, or customer-facing PDFs. A generic English-only helper breaks as soon as you need Hindi rupees, Arabic invoices, or region-specific currency names.

Solution with to-words

import { toCurrency } from 'to-words';

function invoiceWords(amount, localeCode) {
  return toCurrency(amount, { localeCode });
}

invoiceWords(1234.56, 'en-US');
// "One Thousand Two Hundred Thirty Four Dollars And Fifty Six Cents Only"

invoiceWords(1234.56, 'hi-IN');
// "बारह सौ चौंतीस रुपये और छप्पन पैसे"

invoiceWords(1234.56, 'ar-SA');
// "ألف ومئتان وأربعة وثلاثون ريالاً وستة وخمسون هللة"

Multi-Locale Invoice Example

const locales = ['en-US', 'hi-IN', 'es-ES', 'ar-SA'];
const amount = '12500.75';

const totals = locales.map((localeCode) => ({
  localeCode,
  words: toCurrency(amount, { localeCode }),
}));

This pattern works well when a billing system must generate the same invoice in the seller's language, the buyer's language, and a compliance language.

With PDFKit (Node.js)

import PDFDocument from 'pdfkit';
import { toCurrency } from 'to-words';

const doc = new PDFDocument();
doc.pipe(fs.createWriteStream('invoice.pdf'));

const amount = 4500.0;
const words = toCurrency(amount, { localeCode: 'en-IN' });

doc.text(`Amount: ₹${amount.toFixed(2)}`);
doc.text(`Amount in words: ${words}`);
doc.end();

Why This Works Better Than A Custom Helper

Currency names already match the locale config
Decimal handling stays consistent for print and PDF output
The same conversion call works in frontend previews and backend document generation
Large values can use bigint or string input when finance systems exceed safe integer limits

Invoice Amount in Words ​

The Problem ​

Solution with to-words ​

Multi-Locale Invoice Example ​

With PDFKit (Node.js) ​

Why This Works Better Than A Custom Helper ​

Related ​