Hours calculator

An hours calculator that respects the 60-minute hour

This page does three jobs. “Time between two times” is a time duration calculator: start, end, break, and you get the time worked. “Timesheet” totals a week, day by day. “Add or subtract durations” lets you add hours and minutes typed in whatever form you have them. Every result appears as hours and minutes, as decimal hours and, for the first and third blocks, as minutes.

The sums are done in whole minutes in your browser. Nothing is uploaded, and a total above 24 hours keeps counting instead of wrapping round: 40 h 00 min stays 40 h 00 min.

How to use it

1. Time between two times. Fill in “Start”, “End” and, if you took one, “Break (min)”. From 08:30 to 17:15 with a 45-minute break, the result is 8 h 00 min, or 8.00 h, or 480 min.
2. Timesheet. Seven rows are named Monday to Sunday. Enter start, end and break; the “Total” column shows each day and “Grand total” the week. “Add a row” and the × button change the number of rows. “Copy table” puts tab-separated text on the clipboard, ready to paste into a spreadsheet. “Clear all” empties the sheet.
3. Hourly rate (optional). Type a rate and “Amount” shows decimal hours multiplied by that rate.
4. Add or subtract durations. One duration per line: 1:45, 1h45, 1 h 45, 105 min, or 1.75 for decimal hours. Put a minus sign in front of a duration to take it away.
5. Converter. Type in “Hours and minutes”, “Decimal hours” or “Minutes” and the other two boxes follow: 2:20 is 2.33 h and 140 min.

Why 3 h 50 plus 2 h 40 is not 5.90

An hour has 60 minutes, not 100, so times cannot be keyed into an ordinary calculator as 3.50 + 2.40. Done by hand, the method is:

1. Add the minutes: 50 + 40 = 90 minutes.
2. Take out whole hours: 90 minutes = 1 hour 30 minutes.
3. Add the hours, including the one carried over: 3 + 2 + 1 = 6 hours.

The answer is 6 h 30 min, which is 390 minutes or 6.50 decimal hours. A three-part example: 1:45 + 2:30 + 0:50 = 5 h 05 min, that is 305 minutes or 5.08 h.

Minutes to decimal hours

Payroll software and invoices usually want decimal hours: seven and a half hours is 7.5, not 7.30. Divide the minutes by 60 to convert.

Only 15, 30 and 45 minutes convert exactly. The other rows are rounded to two places (5 minutes is 0.0833… of an hour), which is why the tool keeps whole minutes internally and rounds only what it displays.

Using it as a timesheet calculator

Take five days from 08:30 to 17:00 with a 30-minute lunch break. Each day comes to 8 h 00 min and the week to 40 h 00 min, or 40.00 h. With a rate of 12.50, the amount line reads 40.00 × 12.50 = 500.00.

In the United Kingdom, the general rule is that workers should not work more than 48 hours a week on average, unless they have agreed in writing to opt out. That is a broad reference point only: your contract or a workplace agreement may set different hours, and some jobs follow their own rules. The tool does not apply any of this. It works out no overtime rates, no premiums and no pay; the amount is a plain multiplication.

Night shifts. When the end time is earlier than the start time, the tool assumes the shift runs past midnight and says so. From 22:00 to 06:00 is 8 h 00 min; from 21:30 to 05:15 is 7 h 45 min, or 7.75 h.

Frequently asked questions

What is 7 hours 30 minutes as a decimal?

7.5 hours, shown as 7.50. Thirty minutes is half an hour.

What is 2 hours 20 minutes in decimal hours?

20 ÷ 60 = 0.333…, so 2 h 20 min is 2.33 decimal hours, or 140 minutes.

Is my timesheet saved?

Yes. The rows and the rate are kept on your device, in this browser, and come back on your next visit. Nothing is sent anywhere. “Clear all” wipes them.

What if the start and end times are the same?

The duration is 0 h 00 min; the tool does not assume a full 24 hours. If the break is longer than the duration, the row shows “Break longer than the duration”.