Minutes to hours: convert to decimal hours and back
Enter minutes and you get the decimal number an hours calculation works with, plus the clock form. The bottom field converts the other way.
Calculator
Enter what you have. The top field converts minutes to hours, the bottom one converts a decimal number back to minutes.
For example 100 or 450
For example 0.75 or 7.5
Enter a number of minutes to see the hours.
Enter a decimal number to see the minutes.
What this calculator does not do: it does not know how much break to deduct, or whether your employer records time per minute or per quarter hour. That varies by organization and decides which of the two columns above you use.
| Minutes | Hours | Clock |
|---|---|---|
| 10 | 0.17 * | 0:10 |
| 15 | 0.25 | 0:15 |
| 20 | 0.33 * | 0:20 |
| 30 | 0.5 | 0:30 |
| 45 | 0.75 | 0:45 |
| 50 | 0.83 * | 0:50 |
| 90 | 1.5 | 1:30 |
| 100 | 1.67 * | 1:40 |
| 150 | 2.5 | 2:30 |
| 450 | 7.5 | 7:30 |
An asterisk means the decimal is rounded to two places; the real value runs on after the decimal point.
Why payroll wants the decimal
An hourly rate is an amount per hour, and a clock time is not a number of hours. Multiply a rate by 7:30 and nothing sensible comes out; multiply it by 7.5 and it does. That is why payroll tools and timesheets work with the decimal form. The clock form sits next to it so you can check the result.
- 4.5 hours and 4:30 are the same stretch of time, but not the same number
- Add in the decimal column and check in the clock column
- A spreadsheet cell in clock format starts over at 24 hours
Why 20 minutes is not exactly 0.33 hours
An hour has sixty minutes, a two-digit decimal has a hundred hundredths, and sixty does not go into a hundred. So a number of minutes only comes out exactly when it is a multiple of three: 15 minutes is exactly 0.25, 45 minutes exactly 0.75. Ten minutes, on the other hand, is 0.1666…, and 20 minutes becomes 0.3333…. The asterisk in the table marks these cases.
- Three times 20 minutes is exactly one hour, but three times 0.33 is only 0.99
- Six times 20 minutes is 2.00 hours, six times 0.33 only 1.98: a little over a minute of difference
- Rounding each entry gives a different total from adding first and rounding once
From the decimal back to minutes
The other direction is just as common: the timesheet shows a decimal and you want to know how many minutes that is. 0.75 hours is 45 minutes, 7.5 hours is 450 minutes. For 0.33 hours you get 19.8, and the calculator rounds to the nearest whole minute, which is 20.
- Decimal times 60 gives the minutes
- Only hundredths that are a multiple of five give whole minutes
- Anything else is rounded to the nearest minute
Per minute, quarter hour or five-minute step
Which row of the table you use depends on how your workplace records time. Many round to the quarter hour, some to five minutes, and trades often write down exact minutes. That is an agreement within the business, not a law of nature. What matters is that the whole team uses the same step.
- Quarter hours always give clean decimals: 0.25 / 0.5 / 0.75
- Five-minute steps do not: 5, 10, 20, 25, 35, 40, 50 and 55 minutes run on after the decimal point
- One step size for everyone, not per person
Where converting stops
This page converts one unit into another. If you have the start and end of a shift instead, the hours calculator works out the duration, with break and night shifts. If you already have the duration for each day and need the weekly total, add hours sums them, also beyond 24 hours.
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