How long is it from one time to another? Subtract two clock times and get the exact duration in hours and minutes.
To find the time between two clock times, you subtract them — but borrowing minutes across the 60 boundary is where mental math slips. TCalc does true time subtraction: 13:05 − 08:47 correctly borrows and returns 4h 18m.
The result is a real duration you can keep calculating with: subtract a break, multiply it, or convert it to decimal hours, minutes, or seconds with one tap.
Duration between a start and end time.
Tricky minute borrowing handled correctly.
Duration minus a break in one expression.
The reverse question: what time is it 8 hours after 22:00?
Subtract the earlier time from the later one: 17:45 − 09:15 = 8h 30m. In TCalc you type it exactly like that and can subtract breaks in the same expression.
Yes — TCalc has 15 output formats. Switch to the hours format and 8h 30m displays as 8.5h; minutes and seconds formats are one tap away too.
Split at midnight and add the parts (22:00 to 06:00 = 2h + 6h = 8h), or flip the question and add the duration to the start: 22:00 + 8h shows 6:00 AM the next day.