Hours times sixty
One hour is 60 minutes, a fixed relationship inherited from the ancient base-60 counting system. Multiply hours by 60 to get minutes; divide minutes by 60 to get hours. For a mixed time like 2 h 30 min, work each part: (2 × 60) + 30 = 150 minutes.
Common conversions
| Hours (decimal) | Minutes | As h:min |
|---|---|---|
| 0.25 | 15 | 0:15 |
| 0.5 | 30 | 0:30 |
| 0.75 | 45 | 0:45 |
| 1 | 60 | 1:00 |
| 1.5 | 90 | 1:30 |
| 2.5 | 150 | 2:30 |
| 8 | 480 | 8:00 |
| 24 | 1440 | 24:00 |
A standard 8-hour workday is 480 minutes; a full day is 1440.
The decimal-hour trap
- 0.30 hours is not 30 minutes. The decimal part is a fraction of an hour, so 0.30 × 60 = 18 minutes. Thirty minutes is 0.5 of an hour, written 0.50.
- A colon is not a decimal. "2:30" means 2 hours 30 minutes (150 min). "2.30" hours would be 2 hours 18 minutes. They are different numbers.
- Carry the minutes when you add. 2 h 45 min plus 1 h 30 min is not 3 h 75 min. Convert to minutes first: 165 + 90 = 255, which is 4 h 15 min.
Common questions
How many minutes are in an hour?
Exactly 60. To convert hours to minutes, multiply by 60; to go from minutes back to hours, divide by 60. So 3 hours is 180 minutes, and 180 minutes is 3 hours.
How do I convert 1.5 hours to minutes?
Multiply by 60: 1.5 times 60 is 90 minutes. It helps to split it up: 1 hour is 60 minutes and the half hour is 30, which adds to 90.
Is 2.5 hours the same as 2 hours 30 minutes?
Yes. 2.5 is the decimal way of writing 2 hours and 30 minutes, and both equal 150 minutes. The common mistake is reading 2:30 as 2.30 hours, which it is not.
