Hours Between Two Times
Time worked
8.00
- Decimal hours8.00
- Hours and minutes8h 00m
- Total minutes480
Payroll systems usually want decimal hours: 7 hours 30 minutes is 7.50, not 7.30.
Clock time out, decimal hours in
Clock times are base 60 and payroll is base 10, so the conversion between them is the single most common source of small, repeated errors on a time sheet. Half an hour is 0.50, not 0.30. Ten minutes is 0.17, not 0.10. This tool takes a start time, an end time and an unpaid break, and returns the same span three ways: decimal hours for payroll, hours and minutes for humans, and total minutes for checking.
It is the single-shift version of the time card calculator: useful for invoicing a client for one session, checking a single day on a rota, or working out how long anything actually took.
Three worked shifts
A 09:00 to 17:30 shift with a 30-minute unpaid lunch is 510 minutes of clock time minus 30, which is 480 minutes: 8.00 decimal hours, or 8h 00m.
An 08:15 to 16:45 shift with a 45-minute break is 510 minutes minus 45, which is 465 minutes: 7.75 decimal hours, or 7h 45m. Note that 7.75 and 7h 45m are the same quantity written in two number systems — a payroll line reading 7.45 would be twelve minutes short.
A night shift from 22:00 to 06:30 with a 30-minute break is also 480 minutes. The end time is earlier than the start, so it is read as crossing midnight rather than as a negative day, and the answer is 8.00 hours rather than minus 16.
The conversion, in one line
Decimal hours = (minutes between the two times − unpaid break minutes) ÷ 60. Both times are parsed to minutes past midnight; if the end is at or after the start, the span is end − start, and if it is before, the span is end + 1,440 − start.
The result is never negative — a break longer than the shift clamps to zero rather than producing a nonsense figure. For converting minutes in your head, the useful anchors are 15 minutes = 0.25, 20 = 0.33, 30 = 0.50, 40 = 0.67 and 45 = 0.75.
What it assumes
A single span within one 24-hour cycle. A shift longer than 24 hours cannot be expressed by two clock times, and a shift with two separate breaks should have those breaks added together before being entered.
The tool has no view on whether the break should be unpaid, whether the hours attract overtime, or which day an overnight shift belongs to for the purposes of a weekly threshold. Those are policy and law rather than arithmetic. It also does not apply rounding rules: some US employers round clock punches to the nearest quarter hour under the FLSA, which is permitted only where the rounding does not systematically favour the employer over time.
Questions about time spans
How do I convert minutes to a decimal by hand?
Divide by 60. Twenty minutes is 20 ÷ 60 = 0.33 hours; fifty minutes is 0.83. The reverse is multiplying the decimal part by 60, so 7.75 hours is 0.75 × 60 = 45 minutes.
Does an overnight shift need a different setting?
No. Enter the real clock times and the crossing of midnight is detected automatically. The only thing to be careful about is which calendar day the hours are recorded against, which is your employer’s rule rather than a property of the clock.
Why does my employer’s system show a slightly different figure?
Usually punch rounding, a paid rest break included in the shift, or a grace period at the start and end. Compare the raw start and end times first — if those match, the difference is in the break or the rounding policy, not the arithmetic.