Time Between Two Times Calculator
Enter two clock times (HH:MM or HH:MM:SS) and instantly get the difference in hours, minutes and seconds — plus decimal hours, total minutes and total seconds. The default "auto-detect" mode handles overnight shifts by treating an end that is earlier than the start as the next day, ideal for graveyard-shift timesheets, concert runtimes or "how long can I sleep before my flight?".
Midnight handling
If the end is earlier than the start, treat it as the next day (good for overnight shifts).
Please enter a valid number
hh:mm:ss
— crosses midnight negative
Decimal hours
—
Total minutes
—
Total seconds
—
Pure clock-time math, no date involved. For multi-day spans, use the Date Difference tool.
Formula
diff_seconds = (h₂·3600 + m₂·60 + s₂) − (h₁·3600 + m₁·60 + s₁) + 86 400 if mode = force, or (mode = auto AND diff < 0) hh:mm:ss = ⌊|diff| / 3600⌋ : ⌊(|diff| mod 3600) / 60⌋ : (|diff| mod 60) decimal_h = diff_seconds / 3600
- · Times use the 24-hour clock (00:00–23:59:59). No AM/PM toggle — midnight is 00:00.
- · "Auto-detect": adds 24 h when end-time < start-time, the right default for overnight shifts.
- · "Force next day": end is always on the next day; 09:00 → 09:00 = 24 h.
- · "Same day": strict same-day difference. A negative result flags reversed entries.
- · Decimal hours: 8.5 means 8 hours 30 minutes — payroll systems usually expect this format.
- · Pure clock-time math, no date awareness. For spans crossing more than one day, use the Date Difference calculator instead.
Frequently asked
An overnight shift starts 22:30 and ends 06:45 the next morning — how many hours is that?
8 hours 15 minutes — i.e. 8.25 decimal hours. Leave the mode on "Auto-detect": because the end (06:45) is earlier than the start (22:30), the tool wraps around midnight and flips the "crosses midnight" badge on. If you subtract a 1-hour unpaid meal break the net work time is 7.25 h.
My payroll system wants decimal hours — how do I read that off?
After entering the two times, read the "Decimal hours" tile — that is your payroll number. Example: 09:00 → 17:30 shows 8.5 h, which is what most timesheet apps expect. To round to the nearest 0.25 h (the standard 15-minute payroll step), snap to .00 / .25 / .50 / .75.
What is the difference between Auto-detect and Force next day?
Auto-detect only adds 24 h when end < start strictly — daytime shifts (09:00 → 17:00) stay as one-day spans. Force next day always pushes the end onto the next calendar day, so 09:00 → 09:00 becomes 24 h. Use Force when you are billing a flat full-day rental of a car, meeting room or venue and the clock times happen to match.
A film runs 02:21:38 (e.g. Oppenheimer). Starting at 19:30, when does it end?
This tool computes the difference between two times, not "time + duration". Add 02:21:38 to 19:30:00 by hand and the film ends at 21:51:38. You can also use this tool in reverse: enter 19:30 and 21:52 and it shows a 02:22:00 gap, which lines up with the runtime.
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