Decimal Hours Calculator

What a decimal hour is

A decimal hour writes part of an hour as a fraction of 60 minutes. The conversion is minutes divided by 60, added to the whole hours. Nothing else is added: no break, no rounding, and no pay rate. If the time on the card is 7 hours and 30 minutes, the minutes portion is 30/60.

Thirty divided by 60 is exactly 0.5. Seven plus 0.5 is 7.5, which payroll fields usually print as 7.50. The four-decimal display is 7.5000. Both columns agree because one half hour needs no further rounding.

H:MM and decimal hours are two ways to show the same span. 7:30 is the clock reading. 7.50 is the payroll reading. Switching the label does not change how long the person worked. A later rounding step can change the number, and that step is separate from the conversion.

Minutes 0–59 to decimal hours

Each row is one minute count with the hours set to zero, so you can add the row to any whole hour. The middle column shows minutes÷60 to four decimal places. The last column rounds that same quotient to the nearest hundredth. Half of a hundredth rounds away from zero. One minute is 0.0167 to four places and 0.02 to the hundredth. Those are not two different lengths of time.

To convert 8 hours and 6 minutes, read the 6-minute row (0.1000, hundredth 0.10) and add 8. The result is 8.10. To convert 7:30, read the 30-minute row and add 7. The result is 7.50.

6-minute and 15-minute steps

Some payroll screens store tenths of an hour. Six minutes is 0.10, because 6/60 = 0.1. Rounding the clock minute to the nearest multiple of 6, then dividing by 60, is one convention. It is not the same as dividing first and then rounding to a hundredth.

Worked example, 7 hours and 8 minutes. Dividing first: 8/60 = 0.1333 to four places, and the nearest hundredth is 0.13, so the hours are 7.13. Nearest 6-minute step: 8 is 2 minutes from 6 and 4 minutes from 12, so the step is 6 minutes, which is 0.10. That version is 7.10. Nearest 15-minute step: 8 is 8 minutes from 0 and 7 minutes from 15, so the step is 15 minutes, which is 0.25. That version is 7.25. Three labeled results, three different steps. Use the one your payroll field asks for.

Halfway on this page rounds away from zero. For a 6-minute step, a remainder of exactly 3 minutes rounds up to the next tenth. For a 15-minute step, an exact halfway point is 7.5 minutes, which also rounds up. Seven whole minutes is nearer to 0 than to 15, so it stays on the lower quarter. The converter above uses this same halfway rule.

This page does not look up a union contract, a state wage order, or an employee handbook. If the handbook says punches round to the nearest quarter hour, follow that booklet. If it says hundredths with no clock rounding, use the hundredth column and leave the 6-minute and 15-minute lines unused.

A week of H:MM, converted once

Two week totals can disagree by a hundredth. One total adds each day's hundredths. The other adds the raw minutes and divides by 60 at the end. Example: five days of 7:20. Each 20 minutes is 0.3333 to four places and 0.33 to the hundredth. Five hundredths are 1.65, plus 35 whole hours, which is 36.65. Five times 20 minutes is 100 minutes, and 100/60 is 1.6667, which rounds to 1.67. The once-divided week is 36.67. The gap is the rounding, not extra work.

Enter each day as H:MM. Empty days count as zero. The first result sums minutes, then divides. The second result sums the hundredth already taken on each day.

Sum minutes, then divide: 36.6667 (36.67 hundredths). Sum of each day's hundredths: 36.65.

Paste into Excel

When hours are in column A and minutes are in column B, the formula is =A1+B1/60. For 7 and 30, the cell shows 7.5. Format the cell as a number with two decimal places when the payroll sheet wants 7.50.

When the cell is an Excel time (a fraction of a day) rather than a count of hours, multiply by 24: =A1*24. A cell that displays 7:30 as a time of day becomes 7.5 hours after that multiply. Do not also divide by 60 if you already multiplied by 24. That second division would shrink a real 7.5-hour day down to 0.125.

For a week, sum the minute counts first, or sum a helper column that still holds minutes÷60 before you round the total. Rounding every helper cell to two decimals and then summing repeats the 36.65 versus 36.67 gap from the section above.

H:MM on the card, decimal in the payroll field

Keep H:MM when a person is reading a punch line. Keep decimal hours when a payroll box says hours and rejects a colon. The timesheet calculator can show either label for a 7-day grid. The time card calculator prints both next to one shift. This page is the conversion table and the week batch for the decimal side.

Clock-in and clock-out stamps, unpaid lunch, and overnight spans are calculated on those other pages. Bring the finished H:MM here when the only remaining job is the decimal field.