A precise, multilingual home for numbers in words.
AmountToWords is a free set of tools for one deceptively tricky job: writing numbers as words correctly. On a cheque, in a contract, or on an invoice, the words are what legally count — and a small mistake in spelling, punctuation or language convention can hold up a payment.
What we do
The core converter turns any amount into words for cheques, contracts and invoices, in 8 languages: English, Spanish, French, German, Italian, Portuguese, Japanese and Chinese financial numerals (大写). Each language follows its own real rules — French uses a comma decimal and spells centimes, German writes the number as one compound word, Chinese inserts the formal zero characters and ends whole amounts with 整. We validate these edge cases carefully so you can copy the result with confidence.
Our approach
We build one focused tool per topic rather than one cluttered page that does everything poorly. We keep pages fast and lightweight — no heavy frameworks, mobile first — so they load instantly even on a phone. And we keep the interface calm and readable, because a tool you trust with a legal amount should feel that way.
Free to use
Methodology
Every conversion engine on this site is validated in an automated Node.js test harness before release, and the exact script embedded in the final HTML is extracted and re-tested, so the code that ships is the code that passed.
The most recent full run was executed on : 657 assertions, 657 passed, 0 failed, covering all 8 language engines, all 10 language-currency configurations and 5 currencies. The suite is organised in three layers:
- Core language engines — 325 cases across English, Spanish, French, German, Italian, Portuguese, Japanese and Chinese financial numerals: zero, teens, tens, hundreds, thousands, millions and the supported maximum of 999,999,999.99.
- Language-specific rules — 138 cases for grammar that generic converters get wrong: French quatre-vingts agreement, Spanish apocopation (veintiún, ciento un mil), German and Italian ein/un before currency nouns, European Portuguese vocabulary, and Chinese zero-insertion.
- Currency configurations — 101 cases per language-currency pairing: major and minor units, singular and plural forms, zero-cent handling and cheque-context word order.
A further 93 assertions cover the input parser (European number formats, ambiguous-input rejection), letter-case transforms, product boundaries, negative-number handling, cheque-preview integrity and regression guards for previously fixed defects. These are logic-level tests; interactive behaviour is additionally verified by hand on real devices before each release. The full suite is re-run before any change to conversion rules ships.
Every tool here is free, with no accounts and no paywalls. The site may display unobtrusive advertising to cover its running costs; see the privacy page for what that means for your data. You can explore the full set on the tools page.
Get in touch
Found a wording that looks wrong, or want a language or currency added? We genuinely want to hear it — email hello@amounttowords.com.