NumberTally Decimal Hours Converter — Hours to Decimals & Back
Convert decimal hours to hours:minutes and back, with seconds and total minutes. Includes a timesheet-add mode that totals a whole list of entries, and a payroll rounding comparison using the standard 7-minute rule.
Decimal hours → HH:MM
Hours : Min
7:30
Minutes
450
Seconds
27,000
HH:MM → Decimal hours
Decimal hours
7.75
Advanced options
Timesheet-add mode — one entry per line (decimal or H:MM)
Common decimal-to-minutes values
| Decimal | Minutes | Decimal | Minutes |
|---|
How it’s calculated
- Decimal → HH:MM: whole part = hours; fractional part × 60 = minutes. Example: 7.5 → 7 hours + 0.5 × 60 = 7:30.
- HH:MM → decimal: hours + minutes ÷ 60 (+ seconds ÷ 3600). Example: 7:45 → 7 + 45 ÷ 60 = 7.75.
- Payroll rounding (7-minute rule): clock times round to the nearest quarter hour — minutes 1–7 round down, 8–22 round to :15, 23–37 to :30, 38–52 to :45, 53+ up to the next hour. It must average out neutrally over time to stay FLSA-compliant.
Why time cards show decimals
Payroll systems do math in decimals because multiplying “7:30” by an hourly rate is awkward, while 7.5 × $20 is trivial. The conversion is always the same: divide minutes by 60. 15 minutes is 0.25, 30 is 0.5, 45 is 0.75 — and 1 minute is 0.0167, which is why payroll rounds instead of tracking every minute.
The mental shortcut: every 6 minutes is exactly 0.1 hours. So 7:42 is 7 + 42÷60 = 7.7, and you can sanity-check any decimal by asking “how many 6-minute chunks?”
The 7-minute rule, explained
Many employers round clock-in/out times to the nearest 15 minutes. Under the FLSA this is legal only if it does not systematically shortchange workers — rounding 7:53 up to 8:00 must be balanced by rounding 8:07 down to 8:00. The timesheet-add comparison above shows your exact total next to the rounded total so you can see the difference.
Frequently Asked Questions
How do I convert 30 minutes to decimal hours?
Divide by 60: 30 ÷ 60 = 0.5 hours. In general, minutes ÷ 60 = decimal hours — 15 min = 0.25, 45 min = 0.75.
What is 0.75 hours in minutes?
Multiply by 60: 0.75 × 60 = 45 minutes. The fractional part of any decimal-hours value times 60 gives the minutes.
Why does my time card show decimals instead of minutes?
Payroll software multiplies hours by your pay rate, and decimals multiply cleanly while “7:30” does not. 7.5 × $20/hr = $150 — no clock arithmetic required.
Is 7.83 hours the same as 7 hours 50 minutes?
Yes — 0.83 × 60 = 49.8, which rounds to 50 minutes. (Exact: 50 minutes = 0.8333 hours.)
What is the 7-minute rounding rule?
Clock times round to the nearest quarter hour: 1–7 minutes round down, 8–14 up to :15, and so on. It is FLSA-legal only when applied neutrally over time. See the worked comparison in the results above.