How do I calculate the hours between two times?

Enter a start and end time in the Between two times mode. The calculator subtracts the start from the end and shows the elapsed span as HH:MM:SS, plus total minutes, decimal hours, and a readable summary like 8h 30m.

How does the crosses-midnight option work?

When an end time is earlier than the start — say a shift from 22:00 to 02:00 — turning on crosses midnight adds 24 hours to the end, so the tool reports 4 hours instead of a negative span.

What are decimal hours and when should I use them?

Decimal hours express a duration as a single number where minutes are a fraction of an hour: 8h 30m becomes 8.5 and 45 minutes becomes 0.75. They are what most timesheets, invoices, and payroll systems expect.

Can I add or subtract a duration from a specific time?

Yes. Switch to Add / subtract, enter a start time and a duration like 90m, 1h 30m, or 01:30, and the tool returns the new time. It wraps within the day and notes whether the result lands on the next or previous day.

Does the calculator handle seconds, not just minutes?

It does. Times accept an optional seconds field (HH:MM:SS), and both the elapsed span and the add/subtract result are computed to the exact second.

Where are my start and end times processed?

Entirely on your device. The Time Duration Calculator does all the arithmetic in your browser, so the times, durations, and results you work with are never uploaded to ArrayKit or any server.

Time Duration Calculator

Find the elapsed time between two clock times — as HH:MM:SS, total minutes, and decimal hours — right in your browser. The times you enter stay on your device.

The Time Duration Calculator runs entirely in your browser. The start and end times, durations, and results are computed on your device and never leave your machine or reach ArrayKit.

Open the Duration Converter

About Time Duration Calculator

The Time Duration Calculator measures how much time sits between two clock times. Enter a start and end time — HH:MM, or add seconds — and it returns the elapsed span as HH:MM:SS along with total minutes, decimal hours for timesheets, and a plain "8h 30m" summary. Overnight shifts are covered: flip on "crosses midnight" and an end that lands before the start, like 22:00 to 02:00, is counted as the next day. A second mode adds or subtracts a duration from a time, so 23:30 plus 90 minutes rolls forward to 01:00 and tells you it moved to the next day. It is handy for logging work hours, planning shifts, and timing how long a task ran. Every calculation happens on your device — the times you type never leave your browser.

Features

Elapsed time between any two clock times, shown as HH:MM:SS
Total minutes and decimal hours, ready for timesheets and payroll
A "crosses midnight" toggle that counts overnight shifts like 22:00 to 06:00
Add or subtract a duration from a time, with a clear next-day carry
Optional seconds for down-to-the-second spans
Flexible duration entry: type "90m", "1h 30m", or "01:30"
One-tap Now buttons fill in the current time
Runs entirely in your browser with no times sent anywhere

How to use the Time Duration Calculator

Keep "Between two times" selected and enter a start and an end time
Turn on "crosses midnight" if the end time falls on the next day
Read the elapsed HH:MM:SS, total minutes, and decimal hours
Switch to "Add / subtract" to shift a time forward or back by a duration
Copy any result with the button beside it

Example

Input

Start: 22:00
End:   02:00  (crosses midnight)

Output

Elapsed: 04:00:00
Decimal hours: 4  ·  Total minutes: 240

A 22:00–02:00 overnight shift is 4 hours once midnight is crossed.

Common errors & troubleshooting

The elapsed span comes out negative or nothing shows. — The end time is earlier than the start. Turn on "crosses midnight" so an end like 02:00 is treated as the next day and the span goes positive.
Decimal hours read like 8.5 instead of 8:30. — Decimal hours express minutes as a fraction of an hour — 30 minutes is 0.5 h, so 8h 30m is 8.5. Use the HH:MM:SS row when you need clock-style output.
Adding a duration landed on an unexpected day. — The resulting time wraps within a single day and the note beside it shows the carry, for example "next day (+1 day)" when 23:30 plus 90 minutes reaches 01:00.
A bare number in the duration field behaved unexpectedly. — A plain number is read as minutes, so "90" means 90 minutes. Add a unit such as "2h" or use clock form like "01:30" to be explicit.

Frequently asked questions

How do I calculate the hours between two times?: Enter a start and end time in the Between two times mode. The calculator subtracts the start from the end and shows the elapsed span as HH:MM:SS, plus total minutes, decimal hours, and a readable summary like 8h 30m.
How does the crosses-midnight option work?: When an end time is earlier than the start — say a shift from 22:00 to 02:00 — turning on crosses midnight adds 24 hours to the end, so the tool reports 4 hours instead of a negative span.
What are decimal hours and when should I use them?: Decimal hours express a duration as a single number where minutes are a fraction of an hour: 8h 30m becomes 8.5 and 45 minutes becomes 0.75. They are what most timesheets, invoices, and payroll systems expect.
Can I add or subtract a duration from a specific time?: Yes. Switch to Add / subtract, enter a start time and a duration like 90m, 1h 30m, or 01:30, and the tool returns the new time. It wraps within the day and notes whether the result lands on the next or previous day.
Does the calculator handle seconds, not just minutes?: It does. Times accept an optional seconds field (HH:MM:SS), and both the elapsed span and the add/subtract result are computed to the exact second.
Where are my start and end times processed?: Entirely on your device. The Time Duration Calculator does all the arithmetic in your browser, so the times, durations, and results you work with are never uploaded to ArrayKit or any server.

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