Case 1
- Hours
- 8h
- Minutes (0–59)
- 30min
8.50h
Open with these valuesDecimal Hours Converter
8.50h
Result: 8.50 h8 hours 30 minutes is 8.5, not 8.3 — the minutes are sixtieths of an hour, not tenths. Divide the minutes by 60 and add the hours: 15 minutes is 0.25, 20 is 0.33, 45 is 0.75. Payroll asks for this form because it multiplies straight by an hourly rate.
The numbers at a glance
Held fixed: Hours 8 h.
| Minutes (0–59) (min) | Result (h) |
|---|---|
| 20 | 8.33 |
| 25 | 8.42 |
| 30Your value | 8.50 |
| 35 | 8.58 |
| 40 | 8.67 |
Worked examples
Case 2
- Hours
- 1h
- Minutes (0–59)
- 15min
1.25h
Open with these valuesCase 3
- Hours
- 0h
- Minutes (0–59)
- 20min
0.33h
Open with these valuesHow it's calculated
decimal hours = hours + minutes ÷ 60
- StepEnter the whole hours — the 8 in 8 hours 30 minutes.
- StepEnter the minutes, 0 to 59; 75 minutes is 1 hour and 15.
- StepThe minutes are divided by 60 and added to the hours.
- ResultRead the decimal hours, ready to multiply by an hourly rate.
What this number means
Decimal hours are the hours plus the minutes divided by 60, and there is nothing else in the calculation. Take the preset of 8 hours and 30 minutes: 30 ÷ 60 = 0.5, add the 8, and the answer is 8.50 hours. The division is the whole point, because the minute figure on a clock is a sixtieth and not a decimal place. What the converter does not do: it has no seconds, adds up no week from several entries, deducts no break and works out no pay. It takes one duration and returns one number, and the minutes field stops at 59 because minutes here belong to a single hour. The limit that matters most is the display, which is rounded to two decimals. That is the precision of a timesheet, not of the arithmetic: one hundredth of an hour is 36 seconds, so the rounding is good to about 18 seconds. Enough for an invoice — but a third of an hour stays 0.33 and never quite reaches 20 minutes.
Minutes are sixtieths, not tenths
8 hours 30 minutes is 8.5, not 8.3. Divide the minutes by 60 before you add the whole hours.
The quarter hours are worth memorising
15 minutes is 0.25, 30 minutes is 0.5 and 45 minutes is 0.75. A third of an hour, 20 minutes, is 0.33.
The minutes field stops at 59
Minutes belong to a single hour, so 75 minutes is 1 hour and 15 minutes. Enter 1 and 15, and the answer is 1.25.
Why payroll asks for this form
Decimal hours multiply straight by an hourly rate, while the clock format 8:30 does not. That is why most payroll and time-tracking systems store time this way.
Commonly misread
8 hours 30 minutes is 8.3 hours.
It is 8.5 hours. Thirty minutes is half an hour, because 30 ÷ 60 = 0.5 and not 0.3.
Typing 90 into the minutes field gives 1.5 hours.
The field runs from 0 to 59, so 90 minutes has to be entered as 1 hour and 30 minutes. A field taking 90 minutes next to 8 hours would invite a double count nobody notices.
0.33 hours is 33 minutes.
0.33 hours is 20 minutes, because 20 ÷ 60 = 0.3333. A third of an hour has no finite decimal form.
8.5 decimal hours are 850 minutes.
They are 510 minutes. Multiply the decimal hours by 60, or add hours × 60 to the minutes.
Reference table
| Hours, minutes | Spoken | Decimal hours |
|---|---|---|
| 0, 15 | a quarter of an hour | 0.25 |
| 0, 20 | a third of an hour | 0.33 |
| 0, 30 | half an hour | 0.50 |
| 0, 45 | three quarters of an hour | 0.75 |
| 1, 15 | an hour and a quarter | 1.25 |
| 2, 0 | two full hours | 2.00 |
| 8, 30 | a working day | 8.50 |
Questions
How do I convert hours and minutes to decimal hours?
Keep the whole hours, divide the minutes by 60, and add the two together. For example, 8 hours 30 minutes is 8 + (30 ÷ 60) = 8.5 decimal hours.
What is 30 minutes in decimal?
Thirty minutes is 0.5 of an hour, because 30 ÷ 60 = 0.5. The quarter-hours are worth memorising: 15 minutes is 0.25, 30 minutes is 0.5, and 45 minutes is 0.75.
Why do timesheets and payroll use decimal hours?
Decimal hours can be multiplied straight by an hourly rate, while the clock format 8:30 cannot. Paying 8.5 hours at a given rate is a single multiplication, which is why most payroll and time-tracking systems store time this way.
What if I have more than 59 minutes?
Minutes belong to a single hour, so the field runs from 0 to 59. If you have 75 minutes, that is 1 hour and 15 minutes — enter 1 and 15, and the answer is 1.25.
How do I get the total in minutes instead?
Multiply the decimal hours by 60, or add hours × 60 to the minutes; both give the same number. A duration of 8.5 decimal hours is 510 minutes.
Sources and last check
Information, not professional advice.