Hours and minutes to decimal hours
Payroll and timesheets record time in decimal hours, where the part after the decimal point is a fraction of an hour, not a number of minutes. 7 hours 45 minutes is 7.75 hours, because 45 minutes is three quarters of an hour. This calculator converts both ways and computes the pay for that time.
The formulas
- Decimal hours = hours + minutes ÷ 60
- Minutes = decimal part × 60
- Pay = decimal hours × hourly rate
Worked example
You worked 7 hours 45 minutes at $20 an hour:
- 45 ÷ 60 = 0.75.
- Decimal hours: 7 + 0.75 = 7.75 hours.
- Pay: 7.75 × $20 = $155.
Going the other way, 6.4 hours is 6 hours and 0.4 × 60 = 24 minutes.
Conversion table
| Minutes | Decimal hours | Minutes | Decimal hours |
|---|---|---|---|
| 1 | 0.02 | 30 | 0.50 |
| 5 | 0.08 | 35 | 0.58 |
| 10 | 0.17 | 40 | 0.67 |
| 15 | 0.25 | 45 | 0.75 |
| 20 | 0.33 | 50 | 0.83 |
| 25 | 0.42 | 55 | 0.92 |
The classic mistake
Writing 7 hours 30 minutes as 7.30 underpays: 7.30 decimal hours is only 7 hours 18 minutes. Over a year of daily entries, the 12 minutes lost each day add up to about 50 hours. The correct entry is 7.50.
Tenths of an hour
Some employers and law firms track time in tenths of an hour, 6-minute increments: 0.1 for 1 to 6 minutes, 0.2 for 7 to 12 minutes, and so on. Under US rules, rounding is allowed only if it averages out over time and does not systematically reduce pay.
Using decimal hours in spreadsheets
Spreadsheets store times as fractions of a day, so 7:45 is 0.3229. Multiply by 24 to get decimal hours (7.75), and divide decimal hours by 24 to turn them back into a time. Format the cell as a number, not a time, when you multiply by a pay rate.