Which time system is used by default?

Make an array of all ISO 639-1 codes and test each supported one to see if 12-hour clock is true or false.

by David Storey

JavaScript

var ISO639_1 = ["en", "en-GB", "en-US", "en-AU", "en-CA", "en-NZ", "en-ie", "en-za", "en-jm", "en-bz", "en-tt"],
    supportedLocales = Intl.DateTimeFormat.supportedLocalesOf(ISO639_1);

console.clear();

for (var i = 0; i < supportedLocales.length; i++) {

    console.log(new Intl.DateTimeFormat(supportedLocales[i], { minute: "2-digit",
    second: "2-digit"}).resolvedOptions().hour12);

}