To convert minutes to decimal hours, divide the minutes by 60. Fifteen minutes is 0.25 hours, 30 minutes is 0.5 and 45 minutes is 0.75. So 7 hours 45 minutes is 7.75 hours. Payroll and invoices use decimal hours because you can multiply them by an hourly rate.
Key takeaways
- Decimal hours = hours + (minutes ÷ 60).
- 7:30 is 7.5 hours, not 7.3. Mixing the two underpays people.
- For billing in six-minute units, each unit is 0.1 hours.
- Round the final figure, not each step.
What is the formula?
Decimal hours = hours + (minutes ÷ 60)
Example: 7 hours 45 minutes = 7 + (45 ÷ 60) = 7.75 hours
Example: 37 hours 48 minutes at $22.00 an hour = 37.8 × $22.00 = $831.60
To go the other way, multiply the decimal part by 60. So 0.4 hours is 0.4 × 60 = 24 minutes.
Which conversions come up most?
- 0.25
15 minutes
- 0.5
30 minutes
- 0.75
45 minutes
- 0.1
6 minutes
Minutes to decimal hours chart
Decimals are rounded to two places.
| Minutes | Decimal | Minutes | Decimal | Minutes | Decimal | Minutes | Decimal |
|---|---|---|---|---|---|---|---|
| 1 | 0.02 | 16 | 0.27 | 31 | 0.52 | 46 | 0.77 |
| 2 | 0.03 | 17 | 0.28 | 32 | 0.53 | 47 | 0.78 |
| 3 | 0.05 | 18 | 0.30 | 33 | 0.55 | 48 | 0.80 |
| 4 | 0.07 | 19 | 0.32 | 34 | 0.57 | 49 | 0.82 |
| 5 | 0.08 | 20 | 0.33 | 35 | 0.58 | 50 | 0.83 |
| 6 | 0.10 | 21 | 0.35 | 36 | 0.60 | 51 | 0.85 |
| 7 | 0.12 | 22 | 0.37 | 37 | 0.62 | 52 | 0.87 |
| 8 | 0.13 | 23 | 0.38 | 38 | 0.63 | 53 | 0.88 |
| 9 | 0.15 | 24 | 0.40 | 39 | 0.65 | 54 | 0.90 |
| 10 | 0.17 | 25 | 0.42 | 40 | 0.67 | 55 | 0.92 |
| 11 | 0.18 | 26 | 0.43 | 41 | 0.68 | 56 | 0.93 |
| 12 | 0.20 | 27 | 0.45 | 42 | 0.70 | 57 | 0.95 |
| 13 | 0.22 | 28 | 0.47 | 43 | 0.72 | 58 | 0.97 |
| 14 | 0.23 | 29 | 0.48 | 44 | 0.73 | 59 | 0.98 |
| 15 | 0.25 | 30 | 0.50 | 45 | 0.75 | 60 | 1.00 |
Tenths of an hour chart for billing
Many firms bill in six-minute units, each worth one tenth of an hour. Work is rounded up to the next unit.
| Minutes worked | Billed as | Minutes worked | Billed as |
|---|---|---|---|
| 1 to 6 | 0.1 | 31 to 36 | 0.6 |
| 7 to 12 | 0.2 | 37 to 42 | 0.7 |
| 13 to 18 | 0.3 | 43 to 48 | 0.8 |
| 19 to 24 | 0.4 | 49 to 54 | 0.9 |
| 25 to 30 | 0.5 | 55 to 60 | 1.0 |
Which increment to use is covered in how to track billable hours.
What is the most common mistake?
Writing clock time as if it were a decimal.
Right
- 7 hours 30 minutes = 7.5 hours
- 8 hours 15 minutes = 8.25 hours
- 6 hours 40 minutes = 6.67 hours
Wrong
- 7:30 entered as 7.30
- 8:15 entered as 8.15
- 6:40 entered as 6.40
The error always runs against the employee. At $20 an hour, entering 7:30 as 7.30 pays $146.00 where $150.00 is owed. If that happened every working day, it would come to about $1,000 a year for one person.
How do you convert a whole week?
Add the hours and minutes first, then convert once.
| Day | Time worked |
|---|---|
| Monday | 8h 10m |
| Tuesday | 7h 45m |
| Wednesday | 8h 20m |
| Thursday | 8h 05m |
| Friday | 7h 30m |
| Total | 39h 50m |
Add the minutes
10 + 45 + 20 + 5 + 30 = 110 minutes, which is 1 hour 50 minutes.
Add the hours
8 + 7 + 8 + 8 + 7 = 38 hours, plus the 1 hour carried over, makes 39 hours 50 minutes.
Convert once
50 ÷ 60 = 0.83, so the week is 39.83 hours.
Multiply by the rate
39.83 × $22.00 = $876.26.
Converting each day separately and rounding each one can shift the total by a few hundredths. Convert the weekly total where you can.
How do spreadsheets handle it?
Spreadsheets store a time as a fraction of a day. To turn a time value into decimal hours, multiply by 24.
Decimal hours from a duration in cell A2: =A2*24 Hours worked from a start time in B2 and an end time in C2, with an unpaid break in minutes in D2: =(C2-B2)*24-D2/60 Gross pay from decimal hours in E2 and an hourly rate in F2: =ROUND(E2*F2,2)
Format the result cells as numbers, not as times, or the spreadsheet will show a clock value.
Should you round to the quarter hour first?
Not unless your payroll policy says so. Rounding to the nearest quarter hour is allowed under federal rules only if it evens out over time. Software that records exact minutes makes it unnecessary. See the 7-minute rule.
How does BirdsEye help?
BirdsEye records working time automatically in one-minute blocks and totals it for each day, week and project. Time entries export as CSV, so the conversion to decimal hours happens once, in your payroll or billing spreadsheet, from exact minutes. BirdsEye does not run payroll or issue invoices. See reports.
Frequently asked questions
How do I convert minutes to decimal hours?
Divide the minutes by 60. For example, 20 minutes ÷ 60 = 0.33 hours.
What is 45 minutes in decimal hours?
0.75 hours.
What is 7 hours 30 minutes as a decimal?
7.5 hours. It is not 7.3, which would be 7 hours 18 minutes.
How do I convert decimal hours back to minutes?
Multiply the decimal part by 60. For example, 0.6 hours × 60 = 36 minutes.
Why does payroll use decimal hours?
Because pay is hours multiplied by a rate, and you cannot multiply a clock time such as 7:45 directly. The decimal form, 7.75, can be multiplied.