30-seconds-of-code/snippets/formatSeconds.md

title, tags

title	tags
formatSeconds	date,math,string

Returns the ISO format of the given number of seconds.

• Divide s with the appropriate values to obtain the appropriate values for "HH:mm:ss".
• Use Array.prototype.map() to create the string for each value, and pads it to 2 digits.
• Use String.prototype.join(', ') to combine the values into a string.

const formatSeconds = s => {
  if (s < 0) s = 0;
  
  return [s / 3600, s / 60 % 60, s % 60]
    .map(v => `${Math.floor(v).toString().padStart(2, '0')}`)
    .join(':');
};

formatSeconds(-200); // "00:00:00"
formatSeconds(200); // "00:03:20"
formatSeconds(99999); // "27:46:39"