Time to Decimal Hours Converter
Convert clock time (hours, minutes, seconds) to decimal hours and back — the exact numbers payroll and timesheets need.
How it works
Decimal hours = h + m ÷ 60 + s ÷ 3600 · Clock: hours = ⌊dec⌋, minutes = ⌊(dec−hours)×60⌋
Timesheets and payroll systems bill in decimal hours, not hours-and-minutes, because you cannot multiply "2:30" by an hourly rate directly. A minute is 1/60 of an hour and a second is 1/3600, so you divide each unit down to a fraction of an hour and add them. Going the other way, the whole-number part is the hours and the fractional part times 60 gives the minutes.
Worked example
2 hours, 30 minutes and 0 seconds = 2 + 30/60 + 0/3600 = 2.5 decimal hours. Reversing 2.5: the whole part is 2 hours, and 0.5 × 60 = 30 minutes, giving 2h 30m.
Frequently asked questions
Why does payroll use decimal hours?
You cannot multiply "8:45" by an hourly wage, but you can multiply 8.75. Converting time to decimal hours lets pay, invoices and billing be computed with plain arithmetic.
How many decimal hours is 15 minutes?
15 minutes is 15 ÷ 60 = 0.25 hours. Likewise 30 minutes is 0.5 and 45 minutes is 0.75.
Is 2.5 hours the same as 2 hours 50 minutes?
No. 2.5 decimal hours is 2 hours 30 minutes, because 0.5 × 60 = 30 minutes. 2 hours 50 minutes would be about 2.83 decimal hours.
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