Time Difference Calculator

The Time Difference Calculator answers one specific question: how long is it from one clock time to another? Enter a start time and an end time and it shows the gap as hours and minutes, plus the total as decimal hours. It also handles spans that cross midnight, such as a night shift from 22:00 to 06:00. To be clear about what it is not: it measures the interval between two times on the same clock, not the time-zone offset between two cities, and it does not handle dates, daylight saving changes or lunch break deductions.

How to use it

1. Pick or type the starting time in "Start time". The default is 09:00.
2. Pick or type the finishing time in "End time". The default is 18:30.
3. If the end time falls on the next day, tick "End time is the next day". When the end time is earlier than the start time, the tool also treats it as next-day automatically.
4. The "Result" section shows "Difference: Xh Ym" and "Total: N hours" to two decimals.
5. The decimal total is handy for multiplying by an hourly rate or filling in a timesheet.

Worked example

These are real results from the tool's own logic. From 09:00 to 18:30 the difference is 9h 30m, a total of 9.50 hours. From 22:00 to 06:00 the end is earlier than the start, so a day is added automatically, giving 8h 0m and 8.00 hours. A start and end of 10:00 with the box unticked gives 0h 0m. Here is an easy trap: if you also tick "End time is the next day" for 09:00 to 18:30, the result becomes 33h 30m (33.50 hours), because ticking the box always adds 24 hours no matter which time is earlier. For an ordinary same-day span, leave it unticked. To avoid surprises, when the box is ticked and the end is later than the start, a one-line note under the result says the end is counted as the next day (09:00 to 18:30 shows 33h 30m). When start and end are identical and the box is unticked, the result is 0 and a short hint says ticking "End time is the next day" gives 24 hours.

Supported features and known limits

• It compares hours and minutes only, with no dates. A normal result is under 24 hours; ticking the box when the end is later than the start gives 24 hours or more, as in the 33.50 hour example above.
• There is no time-zone handling. If you want to know the offset between two cities, this is the wrong tool.
• Daylight saving changeover days are not accounted for, and the real elapsed time on those days can differ by an hour from the clock difference.
• It cannot subtract a lunch or rest break automatically. Calculate the periods before and after the break separately and add them up.
• Identical start and end times give 0, not 24 hours. To represent a full 24 hours, tick "End time is the next day".
• The time pickers are provided by your browser, so they look different in different browsers. If you clear one of the boxes, the result area asks you to enter both times and the total shows --.
• Seconds are not shown; precision is to the minute.

How do I calculate an overnight shift?

Just enter 22:00 as the start and 06:00 as the end. The tool sees that the end is earlier and adds a day, so you get 8 hours without ticking anything. The checkbox is only needed when the end time is later than the start but you mean the following day, for example 08:00 to 20:00 the next day.

Why is the total shown as a decimal?

It is the minutes divided by 60. For example, 9 hours 30 minutes is 9.50 hours and 9 hours 20 minutes is 9.33 hours. You can use that figure directly for hourly pay calculations.

Can I use it to find the time difference between two cities?

No. The tool contains no time-zone data. It only tells you how long it is between two times on the same clock face.

Why does the result ask me to enter both times?

One of the time boxes was cleared, so the tool could not read a valid time. Choose a time again and the result returns.

Privacy and how your data is handled

The calculation runs entirely in your browser. The times you enter are not sent to a server or stored. Refreshing the page restores 09:00 and 18:30.