Time Duration Calculator

Use this time duration calculator to find the exact difference between two times in hours, minutes, and decimal format. Ideal for work hour tracking, timesheet verification, and shift planning.

Enter Two Times

Time Difference

9h 15m
Total Duration

Hours9
Minutes15
Total Minutes555
Decimal Hours9.25
Total Pay$0.00

What is a time duration calculator?

A time duration calculator computes the exact elapsed time between any two clock times. It outputs results in hours, minutes, total minutes, and decimal hours — the format most time-tracking systems use. It also handles overnight shifts that cross midnight.

The Duration Formula

Duration = End Time − Start Time

For overnight: Duration = (24:00 − Start Time) + End Time

Example Calculation

Start time: 8:30 AM. End time: 5:45 PM on the same day. Elapsed time / duration: 9 hours 15 minutes (555 minutes, or 9.25 decimal hours). Enter an hourly rate to estimate gross pay for this elapsed time.

Overnight Example

Start time: 10:00 PM. End time: 6:00 AM the next day, with “Crosses midnight” selected. Elapsed time / duration: 8 hours (480 minutes, or 8.00 decimal hours).

Common Use Cases

  • Shift planning: Checking the exact length of a newly scheduled shift.
  • Overnight work: Using the "crosses midnight" feature to calculate graveyard shift hours.
  • Task tracking: Freelancers logging start and end times for specific administrative tasks before adding them to a timesheet.

Common Mistakes to Avoid

  • Forgetting AM/PM: A 9:00 AM start and 9:00 PM end on the same day gives 12 hours elapsed. A 9:00 AM start and 9:00 AM end gives 0 hours unless overnight is selected, in which case the duration is 24 hours.
  • Adding breaks: This tool measures raw elapsed time. If you took a 30-minute break, you must manually deduct it or use the work hours calculator instead.

How to Use

Follow these simple steps

1

Enter Start Time

Select or type the starting time.

2

Enter End Time

Select or type the ending time.

3

Check Overnight

If the time period crosses midnight, check the overnight option.

4

View Duration

See the exact difference in hours, minutes, and decimal hours.

Frequently Asked Questions

Quick answers to common questions

How do I calculate time between two times?
Subtract the start time from the end time. Example: start time 8:30 AM, end time 5:45 PM on the same day, elapsed time and duration 9 hours 15 minutes (555 minutes, or 9.25 decimal hours). Our time duration calculator handles this automatically.
What are decimal hours?
Decimal hours express elapsed time as a decimal number. Example: start time 8:30 AM, end time 5:45 PM on the same day, elapsed time and duration 9 hours 15 minutes, or 9.25 decimal hours (15 min ÷ 60 = 0.25).
How do I calculate overnight time?
Check the "Crosses midnight" option. Example: start time 10:00 PM, end time 6:00 AM the next day, elapsed time and duration 8 hours (480 minutes, or 8.00 decimal hours).
What is the difference between elapsed time and work time?
Elapsed time is the total time between two points. Work time subtracts breaks. Use our work hours calculator to deduct breaks from elapsed time.
How do I convert minutes to decimal hours?
Divide minutes by 60. Example: start time 8:15 AM, end time 4:00 PM on the same day, elapsed time and duration 7 hours 45 minutes (465 minutes), or 7.75 decimal hours. The minutes portion is 45 ÷ 60 = 0.75.
Can I use this for shift planning?
Yes! Enter proposed shift start and end times to see exact durations. Great for scheduling and ensuring shifts meet minimum or maximum hour requirements.
How is this different from the work hours calculator?
The work hours calculator includes break deduction and pay estimation. This tool focuses purely on the time difference between two points.
Can I calculate time across multiple days?
This calculator handles up to 24 hours (one full day cycle). For multi-day tracking, use our timesheet calculator to enter each day separately.