Convert Miliseconds to hh:mm:ss.mmm Time in JavaScript

The following JavaScript function converts miliseconds to hh:mm:ss.mmm time format:

const msToTime = miliseconds => {
  const pad = (n, z = 2) => ('00' + n).slice(-z);
  const hh = pad(miliseconds / 3.6e6 | 0);
  const mm = pad((miliseconds % 3.6e6) / 6e4 | 0);
  const ss = pad((miliseconds % 6e4) / 1000 | 0);
  const mmm = pad(miliseconds % 1000, 3);
 
  return `${hh}:${mm}:${ss}.${mmm}`
}

Let's use it to convert the current UTC time:

console.log(msToTime(new Date() % 8.64e7))

If the number of miliseconds is less than 86400000 (i.e. 24 hours), it can be simplified to the following function:

const time = ms => new Date(ms).toISOString().slice(11, -1);