Clock and hours · rules read October 11, 2026
Hours and minutes to decimal hours, and back
Enter hours and minutes to get decimal hours, or a decimal figure to get hours and minutes again.
Written by Radif Partners · How the hours are counted · Editorial policy
7 h 50 min in decimal hours
7.83
7.8333 exactly · 7.80 h = 7 h 48 min
| Total minutes | 470 |
| Decimal, two places (payroll) | 7.83 |
| 7.80 decimal hours in h:mm | 7:48 |
Decimal hours = hours + minutes ÷ 60. 15 minutes = 0.25, 30 = 0.5, 45 = 0.75. How this is calculated.
To turn hours and minutes into decimal hours, divide the minutes by 60 and add the result to the whole hours: 7 hours 30 minutes is 7 + 30 ÷ 60 = 7.5 hours, and 8 hours 45 minutes is 8.75. To go back, multiply the decimal part by 60: 7.3 hours is 7 hours and 0.3 × 60 = 18 minutes, written 7:18. The most expensive mistake on time sheets is treating the two notations as one, so that 7:30 gets typed as 7.30. On a week of five shifts written 7:30, 8:45, 7:50, 8:15 and 6:40, the correct total is 39.00 hours, but reading the minutes as hundredths gives 37.80, and at $18 an hour the worker loses $21.60 that week. The calculator converts in both directions and shows the exact fraction and the two-decimal figure payroll uses.
The 7.30 versus 7:30 trap, measured
A colon separates hours from minutes, which run from 0 to 59. A decimal point separates whole hours from hundredths of an hour, which run from 0 to 99. The two look almost the same on a screen, and when somebody copies a time from a schedule into a spreadsheet, the colon is often replaced by a point without anyone noticing. Every value below was converted both ways by the engine, with the pay difference for one day at $18 an hour.
| Written | Correct decimal | Misread as | Minutes lost or gained | Pay gap at $18/h |
|---|---|---|---|---|
| 7:30 | 7.50 | 7.30 | -12 min | -$3.60 |
| 8:45 | 8.75 | 8.45 | -18 min | -$5.40 |
| 6:15 | 6.25 | 6.15 | -6 min | -$1.80 |
| 7:50 | 7.83 | 7.50 | -20 min | -$6.00 |
| 8:10 | 8.17 | 8.10 | -4 min | -$1.20 |
| 9:20 | 9.33 | 9.20 | -8 min | -$2.40 |
| 5:40 | 5.67 | 5.40 | -16 min | -$4.80 |
| 4:55 | 4.92 | 4.55 | -22 min | -$6.60 |
The error always shortchanges the worker, except at zero minutes, because 100 is larger than 60: any number of minutes divided by 100 is smaller than the same number divided by 60. The loss grows with the minutes, so 8:45 costs much more than 8:10. Over the five-shift week in the summary it reaches 72 minutes. A careful payroll clerk catches it; a spreadsheet formula copied down a column does not.
Converting in both directions by hand
From hours and minutes to decimal: divide the minutes by 60 and keep two decimals. Fifteen minutes is 0.25, twenty is 0.33, forty is 0.67, fifty is 0.83. A few anchors make mental conversion quick: every six minutes is a tenth of an hour, and every three minutes is five hundredths. For anything else, a full chart is on the minutes to decimal hours page.
From decimal back to hours and minutes: keep the whole number as hours, multiply only the fraction by 60, and round to the nearest minute. With 9.85 hours, 0.85 × 60 is 51, so the time is 9:51. With 41.2 hours for a week, 0.2 × 60 is 12, so 41:12. People often skip this step when they read a pay stub, and then wonder why 38.75 hours does not look like the 38:45 their time card shows. Those are the same time.
When several values have to be converted and added, convert each one first and then add the decimals, or add the hours and minutes in their own notation and convert once at the end. Mixing the two in one sum is how most errors start. The time calculator adds a list in hours and minutes if you prefer to stay in that notation.
Where the decimal figure goes next
Decimal hours are what payroll multiplies by the hourly rate, what overtime is counted on, and what most pay stubs print. Under the federal overtime rule, the weekly total is compared with 40 hours, and a conversion mistake near that threshold can hide overtime entirely: a week of 40:45 is 40.75 decimal hours, but typed as 40.45 it shows 0.45 overtime hours instead of 0.75. The rounding regulation allows employers to round punches to set increments, but a notation mistake is not rounding and does not average out. The payroll hours calculator converts a whole week of daily totals at once, and the hours calculator gives the decimal directly from start and end times.