Time Duration Calculator
Calculate the exact number of hours and minutes between two times. Supports 12-hour AM/PM and 24-hour time, automatic midnight crossing, and decimal hour conversion.
Quick Answer: Time Duration Formula
The elapsed duration between two clock times is computed by subtracting start time from end time, adjusting for midnight if necessary:
• Daytime Example: 09:15 AM to 05:45 PM = 8 hours 30 minutes (8.50 decimal hours).
• Overnight Example: 10:00 PM to 06:00 AM = (24:00 − 22:00) + 06:00 = 8.00 hours.
Total Work Hours
35:00
35.00 decimal hrs
Regular Hours
35:00
35.00 decimal hrs
Overtime Hours
0:00
0.00 decimal hrs
Days Worked
5 days
Avg: 7:00/day (7.00h)
Weekly overtime threshold: 40 hours/week (Multiplier: 1.5x). Based on standard US FLSA rules; specific state or contract rules (e.g. CA daily overtime) may apply.
How to Calculate Duration Step-by-Step
1. Enter Start and End Times: Input clock-in and clock-out times in either 12-hour AM/PM or 24-hour format.
2. Subtract Unpaid Lunch or Breaks: If the interval includes breaks, enter total break minutes to see net productive hours.
3. Read Hours & Decimal Equivalents: Review duration in hours and minutes (e.g. 7h 45m) and exact decimal format (7.75h) for direct payroll or billing use.
Frequently Asked Questions
How do you calculate the duration between two times?
Convert both times to 24-hour minutes (Hours × 60 + Minutes) and subtract the start time from the end time. If the end time is numerically less than the start time (crossing midnight), add 1,440 minutes (24 hours) to the end time before subtracting.
How do I calculate hours between two times that cross midnight?
When an interval spans midnight (for instance, 10:30 PM / 22:30 to 6:00 AM / 06:00), calculate the time remaining until midnight (1 hour 30 minutes) and add the time elapsed after midnight (6 hours), totaling 7 hours 30 minutes (7.50 decimal hours). Shiftfy computes this automatically.
How do I convert duration minutes into decimal hours?
Divide the minute component by 60. For example, a duration of 8 hours and 15 minutes is 8 + (15 ÷ 60) = 8.25 decimal hours. A duration of 8 hours and 45 minutes is 8 + (45 ÷ 60) = 8.75 decimal hours.
Can I subtract unpaid breaks from my time duration?
Yes. Enter your total unpaid break or lunch minutes in the break field. The calculator deducts break time directly from elapsed duration to yield net working time.
Does this calculator support 12-hour AM/PM and 24-hour military time?
Yes. Shiftfy features a 12h/24h toggle that formats all clock inputs and duration displays in either standard civilian AM/PM format or 24-hour military notation.
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