num2words is a library that converts numbers like 42 to words like forty-two. It supports multiple languages (see the list below for full list of languages) and can even generate ordinal numbers like forty-second (although this last feature is a bit buggy for some languages at the moment).

The project is hosted on GitHub. Contributions are welcome.

The easiest way to install num2words is to use pip:

pip install num2words

Otherwise, you can download the source package and then execute:

python setup.py install

The test suite in this library is new, so it's rather thin, but it can be run with:

python setup.py test

To run the full CI test suite which includes linting and multiple python environments:

pip install tox
tox

Command line:

$ num2words 10001
ten thousand and one
$ num2words 24,120.10
twenty-four thousand, one hundred and twenty point one
$ num2words 24,120.10 -l es
veinticuatro mil ciento veinte punto uno
$num2words 2.14 -l es --to currency
dos euros con catorce céntimos

In code there's only one function to use:

>>> from num2words import num2words
>>> num2words(42)
forty-two
>>> num2words(42, to='ordinal')
forty-second
>>> num2words(42, lang='fr')
quarante-deux

Besides the numerical argument, there are two main optional arguments, to: and lang:

to: The converter to use. Supported values are:

• cardinal (default)
• ordinal
• ordinal_num
• year
• currency

lang: The language in which to convert the number. Supported values are:

• en (English, default)
• am (Amharic)
• ar (Arabic)
• az (Azerbaijani)
• by (Belarusian)
• ce (Chechen)
• cy (Welsh)
• cz (Czech)
• de (German)
• dk (Danish)
• en_GB (English - Great Britain)
• en_IN (English - India)
• en_NG (English - Nigeria)
• es (Spanish)
• es_CO (Spanish - Colombia)
• es_CR (Spanish - Costa Rica)
• es_VE (Spanish - Venezuela)
• es_GT (Spanish - Guatemala)
• eu (EURO)
• fa (Farsi)
• fi (Finnish)
• fr (French)
• fr_CH (French - Switzerland)
• fr_BE (French - Belgium)
• fr_DZ (French - Algeria)
• he (Hebrew)
• hu (Hungarian)
• id (Indonesian)
• is (Icelandic)
• it (Italian)
• ja (Japanese)
• kn (Kannada)
• ko (Korean)
• kz (Kazakh)
• lt (Lithuanian)
• lv (Latvian)
• no (Norwegian)
• pl (Polish)
• pt (Portuguese)
• pt_BR (Portuguese - Brazilian)
• sl (Slovene)
• sr (Serbian)
• sv (Swedish)
• ro (Romanian)
• ru (Russian)
• te (Telugu)
• tg (Tajik)
• tr (Turkish)
• th (Thai)
• vi (Vietnamese)
• nl (Dutch)
• uk (Ukrainian)

You can supply values like fr_FR; if the country doesn't exist but the language does, the code will fall back to the base language (i.e. fr). If you supply an unsupported language, NotImplementedError is raised. Therefore, if you want to call num2words with a fallback, you can do:

try:
    return num2words(42, lang=mylang)
except NotImplementedError:
    return num2words(42, lang='en')

Additionally, some converters and languages support other optional arguments that are needed to make the converter useful in practice.

For additional information on some localization please check the Wiki. And feel free to propose wiki enhancement.

num2words is based on an old library, pynum2word, created by Taro Ogawa in 2003. Unfortunately, the library stopped being maintained and the author can't be reached. There was another developer, Marius Grigaitis, who in 2011 added Lithuanian support, but didn't take over maintenance of the project.

I am thus basing myself on Marius Grigaitis' improvements and re-publishing pynum2word as num2words.

Virgil Dupras, Savoir-faire Linux