Time Duration Calculator

Find exact hours, minutes and seconds between any two times

Works overnightSeconds precisionInstant result
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Time Duration Calculator

8h 0m 0s
duration
8
Hours
480
Total minutes
28,800
Total seconds
https://howlonguntiltimer.com/time-duration-calculator

How to calculate time duration

Enter a start time and end time using 24-hour or 12-hour format. The calculator instantly returns the hours between the two times, along with the total minutes and total seconds. No button click required — results update as you type.

For shifts that cross midnight — like 10 PM to 6 AM — enable the "crosses midnight" checkbox. The calculator will automatically add 24 hours to the calculation so you get the correct 8-hour result instead of a negative number.

This time duration calculator is ideal for calculating hours worked, timing events, tracking shift lengths, or any situation where you need to know the exact elapsed time between two points.

Common use cases

Hours worked

Calculate your shift duration for timesheet entry, freelance billing, or payroll verification.

Meeting duration

Quickly find how long a meeting ran from start time to end time, in minutes and seconds.

Overnight shifts

Nurses, security staff, and other night shift workers need accurate cross-midnight duration calculations.

Event timing

Find the exact duration of a concert, game, race, or any event with a clear start and end time.

Cooking & timers

Calculate how long something has been cooking or how long until a timer completes from a given start time.

Travel time

Determine the exact elapsed travel time between departure and arrival in hours and minutes.

Example calculations

9am to 5pm
8 hours (standard workday)
8am to 4:30pm
8.5 hours
12am to 11:59pm
23 hours 59 minutes
10pm to 6am
8 hours (overnight shift)
9am to 12pm
3 hours (morning half)
1pm to 5pm
4 hours (afternoon half)

Frequently asked questions

How do I calculate the duration between two times?

Enter a start time and end time using the inputs above. The calculator instantly shows the duration in hours, minutes, and seconds, plus the total minutes and total seconds.

What if my end time is before my start time (e.g. overnight shifts)?

Check the "Duration crosses midnight" option. The calculator will then add 24 hours to the calculation, giving you the correct duration for overnight shifts or time spans that cross into the next day.

How many hours is 9am to 5pm?

From 9:00 AM to 5:00 PM is exactly 8 hours, or 480 minutes, or 28,800 seconds.

How do I calculate hours worked?

Enter your clock-in time as the start and clock-out time as the end. The result shows your exact hours and minutes worked. For multiple shifts, run the calculator once per shift and add the results.

Can I calculate duration across midnight?

Yes. Enable the "crosses midnight" option. For example, 10:00 PM to 6:00 AM would show 8 hours duration instead of trying to calculate a negative number.

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