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Time duration calculator

Work out how much time passes between a start and an end time.

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The Time duration calculator turns Start — hour, Start — minute, End — hour, End — minute into Hours, Minutes, Total minutes, instantly and for free. For instance, with Start — hour = 9, Start — minute = 0, End — hour = 17 and End — minute = 30 it returns Hours = 8, Minutes = 30 and Total minutes = 510.

How to use it

  1. Enter your values: Start — hour, Start — minute, End — hour, End — minute.
  2. Read the result instantly: Hours, Minutes, Total minutes.

Frequently asked questions

What does the Time duration calculator actually compute?

It takes Start — hour, Start — minute, End — hour and End — minute and derives Hours, Minutes and Total minutes from them. The calculation is live as you type, so the result updates on every change.

What information do I need to provide?

4 values: Start — hour, Start — minute, End — hour and End — minute. Nothing else is required — no account, no file upload.

Can you show a worked example?

With Start — hour = 9, Start — minute = 0, End — hour = 17 and End — minute = 30, the calculator returns Hours = 8, Minutes = 30 and Total minutes = 510. Those figures come from running this exact tool, so you can reproduce them by entering the same values.

What happens if I enter larger values?

It moves a lot. Using Start — hour = 18, Start — minute = 5, End — hour = 34 and End — minute = 60 instead, Hours goes from 8 to 16 — which is why it is worth testing a few scenarios rather than trusting a single figure.

What does it give for smaller values?

Scaled down to Start — hour = 5, Start — minute = 1, End — hour = 9 and End — minute = 15, Hours comes out at 4. The relationship is worth checking at both ends before you rely on a single result.

When would I actually use this?

Answering a scheduling question exactly: how many working days until a deadline, what date falls sixty days out, and what time that is for a colleague elsewhere.

What is the most common mistake?

Counting days by subtracting dates and forgetting whether the endpoints are included. Inclusive and exclusive counts differ by one, which is the difference between meeting a deadline and missing it.

What is the difference between the Time duration calculator and the Screen time calculator?

This one returns Hours and Minutes; the Screen time calculator returns Per week (hours) and Per year (hours). That is the whole difference — open the one whose figure you need.

Is there a tool for the next step?

Reading time calculator is the closest one after this: Estimate how long a text takes to read from its word count.

What else is worth having open alongside it?

Speech time calculator and Flight Time Calculator — they come up in the same task often enough to be worth a second tab.

Further reading

All guides →
How-toHow to Add and Subtract Time (Hours and Minutes)Add and subtract hours and minutes reliably. Learn to carry over 60, borrow when subtracting, and handle a result that crosses midnight into the next day.ExplainerReading and Writing Military Time0800 is not “eight o'clock” and not “08:00” — it is “zero eight hundred”, with a zone letter on the end. The four digits, the spoken form, midnight at 0000, the argument about 2400, and the reason 12-hour notation cannot settle noon.GuideThe Pomodoro Method: How Long to Work and How Long to RestTwenty-five and five come from Francesco Cirillo's method, not from a trial. What the research actually measured is task switching and the cost of getting back in — and the reason a fixed interval helps is not that 25 minutes is optimal. Plus what the planner really returns, including the long break it quietly leaves out.ExplainerFour Hours a Day of Screen Is Sixty-One Days a YearFour hours a day is 28 a week and 1,460 a year — 60.8 full days. Three hours is 45.6 days and seven is 106.5. The conversion is arithmetic; what it means is not.ExplainerWhat an Availability Percentage Actually AllowsThree nines sounds like a promise until you divide it into minutes. What 99.9 % buys per year, per month, per week and per day; why the measurement window matters far more than the extra nine; and the two different months this tool uses for the same slug.GuideHours Worked With Breaks: the Two Questions the Arithmetic Cannot AnswerEnd minus start minus break is the easy part. Whether a break is paid and whether it counts as working time are two different questions with different answers by country — plus rounding, where timesheets actually go wrong, and what the tool does with a shift that crosses midnight.