7:30 and 7.30 hours differ by 12 minutes
7:30 means seven hours and 30 minutes: 7 + 30 ÷ 60 = 7.5 hours. Decimal 7.30 hours means seven hours and 18 minutes because 0.30 × 60 = 18. At USD 20 per hour, those durations are USD 150 and USD 146.
Worked comparison
The colon separates a base-60 minutes field; the decimal point separates a fraction of an hour. Convert minutes by dividing by 60, never by 100. This distinction matters when transferring hours into a pay calculation. A display such as 7.3000 remains 7.3 decimal hours; trailing zeros do not turn 30 into minutes.
This table scrolls horizontally on small screens.
| Input meaning | Minutes | Decimal hours | At USD 20/h |
|---|---|---|---|
| 7 h 30 min / 7:30 | 450 | 7.5 | USD 150 |
| 7.30 decimal hours | 438 | 7.3 | USD 146 |
| Difference | 12 | 0.2 | USD 4 |
| 0 h 45 min | 45 | 0.75 | USD 15 |
A mistake to avoid
Copying “7.30” from an hours:minutes field into a decimal-hour pay field silently loses 12 minutes. Negative durations use one sign for the whole duration: hours −1 and minutes 30 means −1.5 hours; hours 0 and minutes −30 means −0.5. Negative minutes with nonzero hours are rejected to avoid conflicting signs.
Apply it to your calculation
- Identify whether the source field expects decimal hours or hours and minutes.
- Use the appropriate direction in the converter; minute magnitude must be below 60.
- Review the converted value before entering pay hours. Converting back rounds to the nearest whole minute, so keep the original if seconds matter.
Example inputs: review, then calculate: Hours ↔ Decimal Converter
Sources and limits
The decimal display has up to four decimal places. This is duration arithmetic, not clock-time arithmetic or a payroll rounding rule. The USD illustration uses a simple hourly rate and does not include taxes or overtime.
Example notes updated: