1function tConvert (time) {
2  // Check correct time format and split into components
3  time = time.toString ().match (/^([01]\d|2[0-3])(:)([0-5]\d)(:[0-5]\d)?$/) || [time];
4
5  if (time.length > 1) { // If time format correct
6    time = time.slice (1);  // Remove full string match value
7    time[5] = +time[0] < 12 ? 'AM' : 'PM'; // Set AM/PM
8    time[0] = +time[0] % 12 || 12; // Adjust hours
9  }
10  return time.join (''); // return adjusted time or original string
11}
12
13tConvert ('18:00:00');1var suffix = hour >= 12 ? "PM":"AM";
2var hours = ((hour + 11) % 12 + 1) + suffix