How to use the hours calculator
- Set the start time and end time (hour, minute, AM/PM). The Now link fills in the current time.
- Enter an unpaid break in minutes, if any.
- Optionally add an hourly rate to see the pay.
- Press Calculate. You get the time worked in hours and minutes, decimal hours, total minutes and a 24-hour dial of the shift.
How hours between two times are calculated
- Convert both times to the 24-hour clock (5:30 PM → 17:30).
- Subtract the start time from the end time.
- If the result is negative, the period runs past midnight – add 24 hours.
- Take off the unpaid break.
\text{Hours worked} = (t_{\text{end}} - t_{\text{start}}) - \text{break}If t_{\text{end}} is earlier than t_{\text{start}}, add 24 hours to it first.
17{:}30 - 9{:}00 = 8\text{ h } 30\text{ min}8\text{ h } 30\text{ min} - 30\text{ min} = 8\text{ h}→ 8.00 decimal hours
- The end time is earlier, so add 24 hours:
(6{:}30 + 24{:}00) - 22{:}00 = 8\text{ h } 30\text{ min} - In decimal hours:
8 + \frac{30}{60} = 8.50
12-hour and 24-hour clock
| 12-hour | 24-hour | 12-hour | 24-hour |
|---|---|---|---|
| 12:00 AM (midnight) | 00:00 | 12:00 PM (noon) | 12:00 |
| 1:00 AM | 01:00 | 1:00 PM | 13:00 |
| 6:00 AM | 06:00 | 6:00 PM | 18:00 |
| 9:30 AM | 09:30 | 9:30 PM | 21:30 |
| 11:59 AM | 11:59 | 11:59 PM | 23:59 |
Decimal hours for payroll
Payroll systems multiply decimal hours by the hourly rate, so 7 hours 45 minutes must be written as 7.75, not 7.45.
\text{Decimal hours} = \text{hours} + \frac{\text{minutes}}{60}\text{Pay} = \text{decimal hours} \times \text{hourly rate}| Time worked | Decimal hours | Pay at 20.00 / hour |
|---|---|---|
| 7 h 15 min | 7.25 | 145.00 |
| 7 h 45 min | 7.75 | 155.00 |
| 8 h 20 min | 8.33 | 166.67 |
| 8 h 30 min | 8.50 | 170.00 |
Totalling a week of shifts
| Day | Start | End | Break | Hours |
|---|---|---|---|---|
| Monday | 9:00 AM | 5:30 PM | 30 min | 8.00 |
| Tuesday | 8:45 AM | 5:15 PM | 30 min | 8.00 |
| Wednesday | 9:00 AM | 6:00 PM | 45 min | 8.25 |
| Thursday | 9:15 AM | 5:30 PM | 30 min | 7.75 |
| Friday | 9:00 AM | 4:00 PM | 30 min | 6.50 |
| Week total | 38.50 | |||
Work out each day here, then add the decimal hours. Some employers round each shift to the nearest 5, 6 or 15 minutes – check your own policy.
To add up durations such as 2 h 45 min + 1 h 30 min, use the Time Calculator.
Frequently asked questions
How do I calculate hours worked between two times?
Subtract the start time from the end time on the 24-hour clock, add 24 hours if the shift crosses midnight, then take off any unpaid break.
How do I calculate an overnight shift?
Just enter the times. When the end time is earlier than the start time, the calculator assumes the shift ends the next day.
What is 7 hours 45 minutes as a decimal?
7.75 hours, because 45 ÷ 60 = 0.75. Payroll uses the decimal value, not 7.45.
What if the start and end times are the same?
That is treated as a full 24-hour period.
Is the break included in the pay?
No. The break is treated as unpaid and taken off before the pay is calculated. Leave it at 0 for a paid break.