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Time calculator
Add or subtract hours and minutes, or add a length of time to a clock time to see when a shift ends, even past midnight. The answer comes in hours and minutes and in decimal hours for payroll.
By Asier Fernández ·
Add or subtract hours and minutes
What time will it be after a number of hours?
How to add hours and minutes by hand
Add the hours and the minutes separately. If the minutes come to 60 or more, take 60 away and add one hour. For example, 7:45 + 4:30 is 11 hours and 75 minutes, which is 12:15. To subtract, borrow an hour when you need it: 12:15 − 4:30 is 11:75 − 4:30, which is 7:45.
For a clock time, add the length of the shift to the start and take 24 hours away if you pass midnight. A 12-hour night shift that starts at 7:00 p.m. ends at 7:00 a.m. the next day; add 30 minutes of unpaid break and it ends at 7:30 a.m.
Minutes to decimal hours
Payroll systems usually want hours as a decimal. Divide the minutes by 60:
| Minutes | Decimal hours | Minutes | Decimal hours |
|---|---|---|---|
| 5 | .08 | 35 | .58 |
| 10 | .17 | 40 | .67 |
| 15 | .25 | 45 | .75 |
| 20 | .33 | 50 | .83 |
| 25 | .42 | 55 | .92 |
| 30 | .50 | 60 | 1.00 |
So 7 hours 45 minutes is 7.75 hours, and 11 hours 20 minutes is 11.33 hours.
Rounding on time clocks
Many employers round punches to the nearest 5 minutes, tenth of an hour (6 minutes) or quarter hour (15 minutes). Federal rules accept this only if it averages out, so that over time employees are paid for all the time they actually work (29 CFR 785.48(b)). Rounding that always favours the employer does not meet that test.
More time tools
To total a whole week of punches with overtime, use the time card calculator. For the hours between a start and end time, the hours calculator; for a 24-hour clock, the military time chart. Shift patterns and their yearly hours are in the shift calendar.
More guides
Figures are worked out from each cycle; rules checked against official sources on . How we calculate
Questions
How do I add hours and minutes?
Add hours and minutes separately, then turn every 60 minutes into an hour. 7:45 plus 4:30 is 11 hours 75 minutes, which is 12 hours 15 minutes.
How do I subtract time?
Subtract the minutes first. If you do not have enough, borrow an hour as 60 minutes. 12:15 minus 4:30 is 11:75 minus 4:30, which is 7:45.
What is 45 minutes as a decimal?
0.75 hours. Divide the minutes by 60: 15 minutes is 0.25, 30 minutes is 0.5 and 45 minutes is 0.75.
What time is it 12 hours after 7 p.m.?
7 a.m. the next day. Add the hours to the start time and take 24 away when you pass midnight.
Is rounding time clock punches legal?
Under federal rules, rounding to the nearest 5, 6 or 15 minutes is accepted only if over time it does not leave employees unpaid for time they worked (29 CFR 785.48(b)).