How does it handle times that cross midnight?

If the end time is earlier than the start time, the calculator assumes the clock rolled over midnight and adds 24 hours automatically. You can also tick the next-day box to force this, which is handy for overnight shifts.

What are decimal hours used for?

Decimal hours express the duration as a single number — for example 7 hours 30 minutes becomes 7.50. This is the format most timesheets and payroll systems use to multiply hours by an hourly rate.

Does it count seconds?

No. The calculator works to the minute, which matches how shifts, meetings and timesheets are normally recorded. The result is shown in hours and minutes, in decimal hours, and as a total minute count.

Time Duration Calculator — Hours & Minutes Between Two Times

Work out exactly how long is between two clock times. Enter a start and an end time to see the duration in hours and minutes, as decimal hours for timesheets, and as atotal minute count — calculated instantly in your browser, even when the span crosses midnight.

How to use the time duration calculator

Start time — enter the time you began, such as the start of a shift, a meeting or a journey.
End time — enter when it finished. If the end is earlier than the start, the tool assumes it ran past midnight and adds a day for you.
End is next day — tick this only when the end time genuinely falls on the following calendar day, so an overnight span is measured correctly.
Read off the duration, the decimal hours and the total minutes — every figure updates the instant you change a value.

Why three different figures?

The same length of time is useful in more than one shape. The hours and minutes figure is the natural way people describe a duration out loud — “7 hours 30 minutes”. The decimal hours figure turns that into a single number, 7.50, which is exactly what payroll and timesheet software expects when it multiplies your hours by a rate of pay. The total minutes figure is the rawest measure of all, perfect for billing in minute increments, working out parking or call charges, or feeding the result into another calculation.

Handling spans that cross midnight

A common headache with time maths is the night shift: clock on at 22:00, clock off at 06:00, and a naive subtraction gives a nonsensical negative number. This calculator solves that two ways. If the end time is at or before the start time, it assumes the clock simply rolled over midnight and adds 24 hours, so 22:00 to 06:00 correctly reads as 8 hours. For anything longer — where the end really is on the next calendar day even though it is later on the clock — you can tick “End time is on the next day” to force the extra 24 hours. Between the two, every overnight or same-day span is measured the way you would on a real clock.

What you can use it for

Work hours & shifts: total a working day, including overnight shifts, ready to drop into a timesheet.
Billing & invoicing: convert a start and finish time into decimal hours to multiply by an hourly rate.
Meetings & events: check how long a session, call or appointment actually lasted.
Cooking, parking & travel: measure any everyday gap between two clock times in plain minutes.

Is it private?

Completely. The times you enter never leave your device — the calculation runs in JavaScript right inside this page, with no server call, no account and no tracking of what you type. Close the tab and nothing is saved.

Frequently asked questions

What happens if the start and end times are the same?

If you enter the same time for both and leave the next-day box unticked, the duration shows as zero. Tick the next-day box to treat it as a full 24-hour span instead.

Can I measure a span longer than 24 hours?

The end-is-next-day option adds a single day, so it covers any span up to 24 hours apart on the clock. For multi-day durations, a date difference tool is the better fit.

Do I need a colon or AM/PM?

No typing format to worry about — the time fields use your browser's built-in time picker, so you just set the hours and minutes and the result updates live.