Time Duration Calculator
Calculate time duration between any two times. Supports multi-day periods and decimal hours.
Add / Subtract Time
Calculating Hours Between Two Times
To find the duration between a start and end time, convert both to minutes from midnight, subtract, and convert back to hours and minutes. From 9:15 to 17:45 is 8 hours 30 minutes. The tricky cases are durations that cross midnight and shifts with unpaid breaks — this calculator handles both, including subtracting break time from the total.
Common Uses
- Working out paid hours on a timesheet.
- Timing how long a task, journey, or event took.
- Adding up billable hours for invoicing.
Decimal Hours for Pay
Payroll often needs hours as a decimal, not hours and minutes: 8 hours 30 minutes is 8.5 hours (30 ÷ 60 = 0.5). To work with calendar dates rather than clock times, use the date calculator.
| Minutes | Decimal hours |
|---|---|
| 15 min | 0.25 |
| 30 min | 0.5 |
| 45 min | 0.75 |
| 10 min | 0.17 (rounded) |
| 20 min | 0.33 (rounded) |
| 40 min | 0.67 (rounded) |
Frequently Asked Questions
Subtract the start time from the end time. Convert to a common unit (minutes or seconds) first. For example: 2:30 PM to 5:15 PM = 2 hours 45 minutes = 165 minutes.
If the end time is earlier than the start time, the duration crosses midnight. Add 24 hours to the end time before subtracting. Example: 11:00 PM to 2:00 AM = 3 hours.
The US standard is 40 hours per week (8 hours per day × 5 days). The EU Working Time Directive caps work at 48 hours per week averaged over 17 weeks.