Hours and Minutes to Decimal
Why 7:45 is 7.75 hours, and how timesheet rounding works.
The Short Answer
An hour has 60 minutes, not 100. So the minutes are sixtieths of an hour: 45 minutes is 45 ÷ 60 = 0.75 hours, and 7:45 is 7.75 hours.
Writing it as 7.45 means 7 hours and 27 minutes. At $20 an hour, that's $149.00 instead of $155.00 for one shift.
Add up hours in decimal →How to Convert
- Split the time into hours and minutes: 7:45 is 7 hours and 45 minutes.
- Divide the minutes by 60: 45 ÷ 60 = 0.75.
- Add the hours back: 7 + 0.75 = 7.75.
- Round to two places if your payroll needs it: 20 minutes is 0.333…, written 0.33.
To go the other way, multiply the decimal part by 60: 0.45 × 60 = 27, so 7.45 hours is 7:27.
| Minutes | Decimal | Minutes | Decimal |
|---|---|---|---|
| 6 | 0.10 | 30 | 0.50 |
| 10 | 0.17 | 40 | 0.67 |
| 12 | 0.20 | 45 | 0.75 |
| 15 | 0.25 | 50 | 0.83 |
| 20 | 0.33 | 55 | 0.92 |
The hours calculator has the full table from 1 to 60 minutes.
Why It Adds Up Over a Week
Five shifts of 7:45 are 38:45, or 38.75 hours. At $20 an hour that's $775.00. Typed into a spreadsheet as 7.45 five times, they become 37.25 hours and $745.00: $30 short, for exactly the same work.
Rounding Rules: the 7-Minute Rule
Many time clocks round punch times. In the US, 29 CFR 785.48(b) accepts recording start and stop times to the nearest 5 minutes, tenth of an hour or quarter of an hour, as long as it doesn't, over time, fail to pay employees for all the time they actually worked.
For quarter hours, the Department of Labor's Fact Sheet #53 spells it out: 1 to 7 minutes may be rounded down, and 8 to 14 minutes must be rounded up. The same fact sheet warns that always rounding down can break minimum wage and overtime rules.
Here is one shift, 8:57 am to 5:08 pm with a 30-minute unpaid break, run through the hours calculator:
| Rounding | Times used | Paid |
|---|---|---|
| None | 8:57 → 5:08 | 7:41 = 7.68 h |
| Quarter hour | 9:00 → 5:15 | 7:45 = 7.75 h |
| Tenth (6 min) | 9:00 → 5:06 | 7:36 = 7.60 h |
State rules can differ from the federal ones. If you think your hours are being rounded unfairly, check the rules where you work. This is not legal advice.
Things That Trip People Up
- Adding times like decimals. 7:45 + 7:45 is 15:30 (15.5 hours), not 14.90.
- Rounding each entry, then adding. Six 10-minute entries are 0.17 hours each when rounded, which adds up to 1.02. Their real total is 60 minutes, exactly 1.00 hour. Add the minutes first, then convert.
- Overnight shifts. 22:00 to 06:30 is 8 hours 30 minutes. Subtracting 22 from 6 gives a negative number; add 24 hours to the end time first.
- Unpaid breaks. Take the break off the shift before converting: 9:00 to 17:30 minus 30 minutes is 8:00, or 8.00 hours.
In Excel
Excel stores a time as a fraction of a day; Microsoft's TIME function page gives 12:00 PM = 0.5 as the example. So multiply by 24: if A1 holds 7:45, =A1*24 gives 7.75. Format that cell as Number; otherwise it may still be displayed as a time.
Frequently Asked Questions
How do I convert hours and minutes to decimal?
Divide the minutes by 60 and add them to the hours. 7 hours 45 minutes is 7 + 45 / 60 = 7.75 hours. 8 hours 20 minutes is 8 + 20 / 60 = 8.33 hours, rounded to two places.
Is 7.45 hours the same as 7 hours 45 minutes?
No. 7.45 hours is 7 hours and 0.45 of an hour, and 0.45 times 60 is 27 minutes, so 7.45 hours is 7 hours 27 minutes. 7 hours 45 minutes is 7.75 hours.
How do I convert decimal hours back to hours and minutes?
Multiply the part after the decimal point by 60. 7.75 hours is 7 hours plus 0.75 times 60, which is 45 minutes. 7.45 hours is 7 hours plus 27 minutes.
What is the 7-minute rule?
It is rounding to the nearest quarter hour. The US Department of Labor's Fact Sheet #53 says time from 1 to 7 minutes may be rounded down and time from 8 to 14 minutes must be rounded up. Federal rules, in 29 CFR 785.48(b), accept rounding only if it does not, over time, underpay employees. State rules can differ.
How do I convert hours and minutes to decimal in Excel?
Excel stores a time as a fraction of a day, so 12:00 PM is 0.5. Multiply the time by 24 to get decimal hours: if A1 holds 7:45, =A1*24 gives 7.75. Format the result cell as Number, not Time.
Why does my timesheet total look wrong?
Often because hours and minutes were added like decimals. 7:45 plus 7:45 is 15:30, which is 15.5 hours, but 7.45 plus 7.45 is 14.9. Convert each entry to decimal first, or add them in an hours calculator that keeps minutes as minutes.