Time between two points
Time Duration Calculator
Find the duration between two times or dates — in hours and minutes, decimal hours, days, or seconds. Or add and subtract a duration from a start time. Live, offline-capable, no signup.
- Hours & minutes
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- Decimal hours
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- Total minutes
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- Total seconds
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- Total days
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- Weeks & days
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A free time duration calculator for hours between two times
Enter a start and an end, and the calculator reports the interval in every unit people actually use. Decimal hours for payroll. Hours and minutes for a schedule. Total minutes or seconds for logging. Weeks and days for a project timeline. One answer, six formats, computed the instant you type — no calculate button, no account, no upload.
The head-term intent for this page is time duration calculator, but people ask the same question in a dozen ways: how many hours between two times, how to calculate hours between two dates, elapsed time from A to B, work time from start to finish. Every phrasing lands on the same result, because the underlying arithmetic is the same.
How to calculate the duration between two times
The method is a subtraction with two wrinkles.
- Convert both times to 24-hour form so there is no AM/PM to fumble.
- Subtract the start from the end. If the end is smaller, the shift crossed midnight — add 24 hours.
- Convert leftover minutes to a fraction of an hour by dividing by 60 for decimal hours.
By hand, 09:00 to 17:30 is 17:30 − 09:00 = 8 hours 30 minutes, and 30 ÷ 60 = 0.5, so 8.50 decimal hours. The calculator does it in one step and keeps every unit visible so you can copy whichever your payslip or scheduler wants.
Overnight and multi-day spans
For an overnight shift, the clock-out is on a later calendar day. Use the date pickers on each side and the tool crosses midnight automatically. From 22:00 on Monday to 06:00 on Tuesday is 8 hours. Over a longer window — 1 September 09:00 to 15 September 17:30 — it reports 2 weeks 0 days 8 hours 30 minutes, plus the running totals in every other unit.
Add or subtract a duration from a time
A common variant of the same query is “what time is it three hours from now” or “what time was it ninety minutes ago”. Switch to theAdd or subtract mode above and the tool answers both. Adding 90 minutes to 22:30 produces 00:00 the next day; subtracting 90 minutes from 00:30 produces 23:00 the day before. No off-by-one across midnight.
Decimal hours, minutes, days — every unit at once
The output block lists six formats because different jobs need different ones. A timesheet wants hours and minutes. Payroll wants decimal hours. A logging system may want total seconds. A project brief may want weeks and days. Rather than convert by hand, pick the row that matches what you are pasting into.
| Time span | H & M | Decimal hours | Total minutes |
|---|---|---|---|
| 09:00 → 17:30 | 8h 30m | 8.5 | 510 |
| 09:45 → 14:30 | 4h 45m | 4.75 | 285 |
| 22:00 → 06:00 (overnight) | 8h | 8 | 480 |
| 08:00 → 20:00 | 12h | 12 | 720 |
| 1 Sep 09:00 → 15 Sep 17:30 | 344h 30m | 344.5 | 20,670 |
Time between two dates
For date-only intervals, set both times to 00:00. From 1 January to 31 December is 364 days, or 52 weeks 0 days — the calendar-week math you would otherwise reach for a spreadsheet to do. The result also converts to hours (8,736) and minutes (524,160), which is useful when a contract or SLA is written in one of those units.
Why the arithmetic runs in UTC
Daylight-saving transitions add or lose an hour on the calendar in your local zone. A naïve subtraction of two local times across a spring-forward Sunday would report 23 hours where 24 were actually elapsed. This tool converts each datetime to UTC before subtracting, so DST cannot bite you. That matters for scheduling, contract windows, and payroll periods that straddle March or November.
Related calculators
- Hours to decimal calculator — turn 7:45 into 7.75 and back, with a full minutes chart.
- Military time converter — 24-hour ↔ 12-hour with the full military time chart.
- Time card calculator — turn a whole week of clock-in and clock-out times into hours, breaks, overtime, and pay.
- Overtime calculator — split a week into regular and overtime hours.
- How to calculate hours worked — the full method by hand, including overnight shifts.
Frequently asked questions
How do I calculate the duration between two times?
Enter the start time and the end time and the duration appears at once. From 9:00 to 5:30 is 8 hours 30 minutes, or 8.5 decimal hours. The calculator shows every unit — hours and minutes, decimal hours, total minutes and seconds, days, weeks — because different jobs need different formats.
How many hours between two times?
Subtract the start from the end. If the end is on the next day (or later), add the intervening days first. From 09:00 Monday to 17:30 Monday is 8.5 hours. From 22:00 Monday to 06:00 Tuesday is 8 hours — the calculator crosses midnight automatically once you pick each side.
How do I calculate time duration between two dates?
Pick a full date and time on each side. The calculator reports weeks, days, hours, minutes and seconds, plus each unit as a running total. From 1 September 09:00 to 15 September 17:30 is 2 weeks 8 hours 30 minutes, or 344.5 hours, or 20,670 minutes.
How do I add or subtract a duration from a time?
Switch to the “Add or subtract a duration” mode above. Pick a start time, enter hours and minutes, and choose add or subtract. The tool wraps past midnight in either direction — subtracting 90 minutes from 00:30 gives 23:00 the day before.
How many hours is 9:45 to 2:30?
4 hours 45 minutes, or 4.75 decimal hours. This holds whether you read it as 9:45 AM to 2:30 PM or an overnight 9:45 PM to 2:30 AM — both come to the same length.
How is elapsed time calculated across midnight?
The end datetime is treated as a full point in time, not just a clock reading, so crossing midnight is automatic when you use the date pickers. This tool does the maths in UTC internally so daylight-saving transitions cannot silently add or subtract an hour on you.
What is the difference between duration and elapsed time?
In everyday use they are the same: the length of the interval between two moments. In physics or a race, elapsed time may include pauses that a duration excludes, but for scheduling, invoicing, and timesheets the calculator uses them interchangeably.
Can I get the answer in decimal hours for payroll?
Yes. Every result includes decimal hours alongside hours-and-minutes, because payroll systems run on decimals. If you need the reverse — a decimal figure converted back to hours and minutes — the hours to decimal calculator does that specifically.