You can use a Computed Label field to calculate the time difference between two time picker fields. In the example below, we have a time field with the key "time1" and another with the key "time2".

In the example below, we calculate the total hours between the two date values. You can adjust the formula to convert to minutes, seconds or days according to your needs.

ADD THIS TO YOUR CALCULATION FIELD

var date1 = dateFromString($time1$);

var date2 = dateFromString($time2$);

var hours = Math.abs(date2 - date1) / 36e5;

return hours;

function dateFromString(isoDateString) {

var parts = isoDateString.match(/\d+/g);

var isoTime = Date.UTC(parts[0], parts[1] - 1, parts[2], parts[3], parts[4], 0);

var isoDate = new Date(isoTime);

return isoDate;

}