JSFiddle - React, Tailwind, and code Playground

JavaScript

var time24To12 = function(a) {
    return (new Date("1955-11-05T" + a + "Z")).toLocaleTimeString("bestfit", {
        timeZone: "UTC",
        hour12: !0,
        hour: "numeric",
        minute: "numeric"
    });
};
//some examples:
console.log(time24To12('00:00'));
console.log(time24To12('00:01'));
console.log(time24To12('13:00'));
console.log(time24To12('24:00'));
console.log(time24To12('12:00'));
console.log(time24To12('17:00'));
console.log(time24To12('23:59'));