Playground

This page runs the real @miloun/cosmo JS port (vendored under javascripts/cosmopolitan/) entirely in your browser. Because the library is built on the standard Intl API, every value below comes straight from your own browser's ICU — there is no server, and no results are precomputed.

Pick a locale (or type any BCP-47 tag), optionally set a time zone and currency, and the table updates live. Methods your runtime can't back simply show the error in place, so you can see exactly what Intl exposes where you are.

Other ports

The PHP, Python, and Java ports produce the same output (ICU is the common engine); only the call syntax differs — and they add the raw-ICU methods Intl can't reach (parsing, transliteration, spellout, …). See the API reference and Feature parity for the cross-language picture.