Time Zone Difference Calculator - Hours Between Two Times

    Night shift ends at 06:00, started at 22:00 - how many hours was that? Enter two clock times and get the absolute difference in hours, minutes, seconds and decimal format. Works across midnight.

    Parameters

    Enter data for calculations

    24-hour format (e.g. 08:00, 14:30, 23:45)

    24-hour format (e.g. 17:00, 22:15, 06:30)

    Form progress0 / 2 fields

    💡 Fill in all required fields to unlock the calculate button

    Your shift started at 22:00 and ended at 06:30

    That is 8 hours and 30 minutes. Simple enough on paper, but mental arithmetic across midnight gets messy fast - especially when payroll needs a decimal number, not "about eight and a half hours." This calculator takes any two clock times and returns the absolute gap in every format you might need: hours and minutes, a decimal value, and total minutes and seconds.

    Quick example: Enter 14:00 and 17:45 - result: 3 hr 45 min (3.75 decimal hours, 225 minutes, 13,500 seconds).

    When does midnight change everything?

    Without the midnight checkbox, the calculator finds the absolute difference between two times within the same day. Check the box, and it calculates the forward span from time 1 to time 2 across the date boundary. The table below shows how the same pair of times produces different results depending on the setting:

    Time 1 Time 2 Same day Across midnight Use case
    22:00 06:00 16 hr 0 min 8 hr 0 min Night shift
    23:30 02:15 21 hr 15 min 2 hr 45 min Evening event
    08:00 17:00 9 hr 0 min 9 hr 0 min Regular work day
    20:00 08:00 12 hr 0 min 12 hr 0 min 12-hour rotation

    People also ask

    How many hours is 08:00 to 17:00?
    The difference is 9 hours and 0 minutes, or 9.00 decimal hours. That equals 540 minutes or 32,400 seconds.
    What is the difference between this and the Duration Calculator?
    The Duration Calculator measures elapsed time from a defined start to a defined end. This tool finds the absolute gap between any two clock readings - the order does not matter (unless you check the midnight box). Both give the same numeric answer for same-day spans.
    How do I calculate the difference across midnight?
    Enter the earlier time as "First time" (e.g. 22:00), the later time as "Second time" (e.g. 06:30), and check "Time crosses midnight." The calculator adds 24 hours to the span, giving 8 hr 30 min instead of 15 hr 30 min.
    Can I enter times in 12-hour (AM/PM) format?
    The input fields use 24-hour format only. Convert AM/PM manually: 1:00 PM = 13:00, 11:30 PM = 23:30, 12:00 AM (midnight) = 00:00. For quick conversions, try the Minutes to Hours Converter.
    What is a decimal hour?
    A decimal hour expresses time as a single number. 7 hours 30 minutes = 7.50 decimal hours. Payroll systems prefer this format because multiplication is straightforward: 7.50 x $20/hr = $150.00.
    What happens if I enter the same time twice?
    The result is 0 hours, 0 minutes, 0 seconds. The calculator suggests checking the midnight box if you intended a full 24-hour cycle.

    Scenarios where this calculator saves time

    Freelancer invoicing
    Started a task at 09:15, finished at 13:40.
    Difference: 4 hr 25 min (4.42 h)
    Hospital shift handover
    Day nurse: 07:00 to 19:30.
    Difference: 12 hr 30 min (12.50 h)
    Flight travel time
    Departure 14:20, landing 22:05.
    Difference: 7 hr 45 min (7.75 h)
    Warehouse night shift
    Clock in 22:00, clock out 06:00 (midnight).
    Difference: 8 hr 0 min (8.00 h)
    Study session tracking
    Started at 20:00, stopped at 23:45.
    Difference: 3 hr 45 min (3.75 h)

    How to use - step by step

    1. First time - type or select the first clock reading in HH:MM format (e.g. 08:00).
    2. Second time - type or select the second clock reading (e.g. 17:30).
    3. Crosses midnight - if the span goes past 00:00, enable this checkbox.
    4. Read the results - hours, minutes, decimal value, total minutes and total seconds.

    AM/PM to 24-hour conversion

    12-hour 24-hour 12-hour 24-hour
    12:00 AM 00:00 12:00 PM 12:00
    1:00 AM 01:00 1:00 PM 13:00
    6:00 AM 06:00 6:00 PM 18:00
    9:00 AM 09:00 9:00 PM 21:00
    11:30 AM 11:30 11:30 PM 23:30

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