Time Duration Calculator
This time duration calculator finds how much time passes between a start and an end time, and it does what a plain answer can't: stack several segments, subtract breaks, and handle shifts that run past midnight. Enter your times and you'll get the total in hours and minutes and in decimal hours, with a live timeline of your day.
- Multiple segments
- Overnight shifts
- Break deduction
- Decimal hours
- Live timeline
Last updated July 15, 2026 Runs in your browser, no sign-up Reviewed by the Calcowa team
That's 8.00 decimal hours, across 2 segments.
Each bar is a segment across the 24-hour day; break time is shown lighter.
How to find the duration between two times
The duration between two clock times is just the end minus the start. The only trick is midnight: when the end time is earlier than the start, the period has rolled into the next day, so you add 24 hours before subtracting. From 9:00 to 17:00 is a clean 8 hours; from 22:00 to 6:00 the clock passes midnight, and adding 24 hours to the 6:00 gives 30:00, minus 22:00, for 8 hours. Breaks come off the top, and multiple segments simply add together.
Working out a split shift with a break
Say you worked 9:00 to 13:00, then 14:00 to 18:30 with a 30-minute break in the afternoon:
- 1
Measure each segmentThe morning is 9:00 to 13:00, which is 4 hours. The afternoon is 14:00 to 18:30, which is 4 hours 30 minutes.
- 2
Subtract the breaksTake 30 minutes off the afternoon segment, leaving 4 hours 0 minutes.
- 3
Add the segments4 hours plus 4 hours is 8 hours of worked time for the day.
- 4
Convert to decimal if neededFor payroll, 8 hours 0 minutes is 8.00 decimal hours, ready to multiply by an hourly rate.
Minutes to decimal hours
Timesheets and invoices want decimal hours, so it helps to know the common conversions. Divide the minutes by 60: 15 minutes is 0.25, 30 is 0.5, 45 is 0.75.
| Minutes | Decimal hour | Minutes | Decimal hour |
|---|---|---|---|
| 10 min | 0.17 | 35 min | 0.58 |
| 15 min | 0.25 | 40 min | 0.67 |
| 20 min | 0.33 | 45 min | 0.75 |
| 30 min | 0.50 | 50 min | 0.83 |
Adding a duration to a clock time instead? The time calculator adds and subtracts times, and the time card calculator totals a whole week of shifts with pay.
Frequently asked questions
Subtract the start time from the end time. If the end is earlier than the start, the period runs past midnight, so add 24 hours before subtracting. For example, 9:00 to 17:00 is 8 hours, while 22:00 to 6:00 crosses midnight and comes to 8 hours as well. This time duration calculator does the arithmetic for you and also lets you add several segments and subtract breaks.
Yes. When the end time is before the start time, the calculator assumes the segment runs into the next day and adds 24 hours automatically. So a shift from 10:00 PM to 6:30 AM is read as 8 hours 30 minutes, not a negative number. You'll see each segment's duration next to it so nothing is hidden.
Use the Add segment button to stack as many start and end pairs as you need, and the calculator sums them into one total. This is handy for a split shift, a day with several meetings, or adding up study or billable hours across the day. Each row can also have its own break to subtract.
Decimal hours express time as a single number instead of hours and minutes, so 8 hours 30 minutes becomes 8.5. Payroll systems, invoices, and timesheets usually want decimal hours, because you multiply them straight by an hourly rate. The calculator shows both the hours-and-minutes total and the decimal version so you can use whichever you need.
Enter the unpaid break in minutes for any segment and it's subtracted from that segment's duration before everything is totaled. A 9-to-5 shift with a 30-minute lunch becomes 7 hours 30 minutes of worked time. Leave the break at zero if the whole period counts.
Yes. A time calculator adds or subtracts a duration to a clock time, like '3:15 plus 2 hours 40 minutes.' This tool measures the elapsed time between two clock times, across as many segments as you like, which is what you need for shifts, hours worked, and how long something took.
Related calculators
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Time card calculatorA full week of shifts and pay.
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Add your segments above, or browse the full date and time hub.