Decimal Hours Calculator
Convert hours and minutes to decimal hours, or convert decimal hours back into hours and minutes.
What are decimal hours?
Decimal hours express a duration as one number. For example, 1 hour and 30 minutes is 1.50 hours. The decimal part is a fraction of an hour, not minutes written after a decimal point.
How to convert minutes to decimal hours
Divide the minutes by 60, then add the result to the whole hours. Thirty minutes is 30 / 60 = 0.50 hours. Twenty minutes is 20 / 60 = 0.3333 hours when shown to four decimal places.
Decimal hours formula
Decimal hours = hours + (minutes / 60)
When converting back, the whole number is hours. Multiply the remaining fraction by 60 and round to the nearest minute.
Decimal hours conversion examples
| Minutes | Decimal hours |
|---|---|
| 5 | 0.0833 |
| 10 | 0.1667 |
| 15 | 0.25 |
| 20 | 0.3333 |
| 30 | 0.50 |
| 45 | 0.75 |
| 50 | 0.8333 |
| 55 | 0.9167 |
Decimal hours vs hours and minutes
8 hours and 20 minutes is exactly 8 hours 20 minutes, and approximately 8.33 decimal hours. The expanded value, 8.3333, keeps the conversion clear because 8.33 alone rounds the duration.
Worked examples
1h 30m = 1.50 decimal hours. Divide 30 by 60 and add it to 1.
8.3333 decimal hours is about 8h 20m. The fractional hour converts to 19.998 minutes, which rounds to 20 minutes.
Frequently asked questions
Why is 30 minutes written as 0.50 hours?
An hour has 60 minutes, so 30 / 60 = 0.5. The calculator shows two decimal places by default as 0.50.
What happens when the conversion needs more than two decimals?
The result keeps up to four decimal places when useful. The calculator also explains when converting a rounded decimal back requires rounding to the nearest minute.
Can I enter negative hours?
No. Enter a nonnegative duration. Negative values are rejected so the conversion remains unambiguous.