Decimal Hours Calculator
Convert between standard hours-and-minutes format and decimal hours — the format most payroll and invoicing systems expect (e.g. 7:30 becomes 7.5).
Also covers: hours to decimal, decimal hours
Decimal Hours Calculator
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View on AmazonHow the Decimal Hours Calculator works
- Choose the conversion direction (hours-to-decimal or decimal-to-hours).
- Enter your value.
- Read the converted result instantly as you type.
Formula / logic
Decimal hours = hours + (minutes ÷ 60). To reverse it: minutes = decimal remainder × 60.
Worked example
3 hours 45 minutes → 3 + (45 ÷ 60) = 3.75 decimal hours. Reverse: 3.75 → 3 hours + (0.75 × 60) = 45 minutes.
Frequently asked questions
Why do payroll systems use decimal hours?
Decimal hours (like 7.5 instead of 7:30) are easier to multiply by an hourly rate, which is why most timesheet and payroll software store time this way.
How do I convert 45 minutes to decimal?
45 minutes is 0.75 of an hour, so 3 hours 45 minutes becomes 3.75 in decimal form.
Why do payroll systems use decimal hours instead of hours:minutes?
Decimal hours multiply cleanly against an hourly rate (e.g. 7.5 × $20 = $150), which is simpler for spreadsheets and payroll software than hours:minutes format.
How do I convert 20 minutes to decimal?
20 minutes ÷ 60 = 0.33, so 20 minutes is roughly 0.33 of an hour.
Is the Decimal Hours Calculator free to use?
Yes — every calculator on this site is free, with no sign-up or download required.