Time Duration Calculator
Calculate elapsed time between two times of day. Deduct break time to find net hours worked.
Gross vs. Net Time
Gross time is the total clock time from start to end. Net time is gross time minus any break periods. For employment purposes, only net time is compensable — the time you were actually working rather than on a rest break.
For example, a shift from 8:00 AM to 5:00 PM with a 45-minute lunch break has a gross duration of 9 hours and a net duration of 8 hours 15 minutes (8.25 decimal hours). Multiplied by an hourly rate of $20, the gross pay would be $165.00.
Hours to Decimal Conversion
| Minutes | Decimal Hours |
|---|---|
| 15 min | 0.25 |
| 30 min | 0.50 |
| 45 min | 0.75 |
| 1 hr 00 min | 1.00 |
| 1 hr 15 min | 1.25 |
| 1 hr 30 min | 1.50 |
| 7 hr 30 min | 7.50 |
| 8 hr 00 min | 8.00 |
Formula: decimal hours = hours + (minutes ÷ 60)
Frequently Asked Questions
How does the time duration calculator work?
The calculator converts both start and end times to minutes since midnight, subtracts the start from the end, and deducts any break time. If the end time is earlier than the start time, it assumes the shift crossed midnight and adds 24 hours (1,440 minutes) to the end time before subtracting.
What are decimal hours and why are they useful?
Decimal hours express the duration as a single number — for example, 7 hours and 30 minutes is 7.5 decimal hours. This format is required for timesheet software, payroll systems, and billing platforms that multiply hours by an hourly rate. Always use decimal hours when calculating pay.
Can it handle overnight shifts?
Yes. If your end time is earlier than your start time (for example, 10:00 PM to 6:00 AM), the calculator automatically treats this as an overnight shift and calculates the correct duration of 8 hours.
How should I enter break time?
Enter the total break duration in minutes. For example, a 30-minute lunch break is 30. The calculator subtracts this from the gross duration to give you net working time. If there is no break, leave it as 0.
What is the maximum shift duration supported?
The calculator supports durations up to 24 hours. For multi-day shifts, use the Work Hours Calculator which supports up to 7 days with separate entries per shift.