I need to know how to add/subtract time. I'm creating a numpad that will display the time in increments(1:00,5:00,10:00 so on and so forth). The user only needs to see the time he/she inputs.I can do that.But what I cant do is to so the sum. I suppose I could convert time in to ticks but that is lost on me. Here I have an example of what I'm working on: (03:25-03:45=00:20) then (09:00+21:00=11:40) As you see I'm using 24 hour display and I subtracted the 20min from the run time of 12 hours.