Time to Decimal Conversion
Need a simple way to turn times like 7:30 or 1:15:30 into a single, easy-to-use number? You're in the right place. This comprehensive time to decimal conversion guide shows how to convert clock time to decimal hours, when and how to round, and quick methods for Excel and Google Sheets. It's clear, practical, and perfect for payroll, billing, and project tracking.
What is decimal time conversion?
Decimal hours express time as one number with a fractional part instead of minutes and seconds. For example, 7 hours 30 minutes becomes 7.5 hours. This time to decimal conversion format is easy to add up, multiply by rates, and drop into reports or invoices.
All you need is one simple rule that turns minutes and seconds into fractions of an hour for accurate time to decimal conversion. This decimal time conversion method simplifies payroll calculations and project time tracking.
The core time to decimal conversion formula (with quick examples)
Decimal hours = h + m/60 + s/3600
- 07:30 → 7 + 30/60 = 7.5
- 08:45 → 8 + 45/60 = 8.75
- 01:15:30 → 1 + 15/60 + 30/3600 = 1.2583
- 12:05 → 12 + 5/60 = 12.0833
This time conversion to decimal formula works for any time format, making it the standard approach for converting time to decimal hours across industries.
Step-by-step time to decimal conversion process
- Split the time into hours, minutes, and (if needed) seconds.
- Turn minutes into hours by dividing by 60, and seconds by dividing by 3600.
- Add them together: hours + minutes/60 + seconds/3600.
- Apply your rounding rule (for example, 2 decimals) for consistent totals in your time to decimal conversion.
Rounding made simple for time to decimal conversion
Pick one policy and use it consistently:
- Two-decimal rounding: Round to 0.01 hour (e.g., 7.504 → 7.50). Common for payroll and billing.
- Fixed increments: Round to steps like 0.1, 0.25, or 0.5 hour. For example, 7.12 → 7.1 (0.1 step) or 7.12 → 7.0/7.25 (0.25 step).
- Direction rules: Use half-up, always up (ceiling), or always down (floor) as your policy requires.
Write the rule into your timesheet guide so totals match across the team.
Excel: tiny formulas for time to decimal conversion
Excel stores time as a fraction of a day (1 day = 24 hours). If A1 has a valid time value:
- Convert to hours:
=A1*24 - Round to 2 decimals:
=ROUND(A1*24, 2) - By parts:
=HOUR(A1) + MINUTE(A1)/60 + SECOND(A1)/3600
If your input is text like "7:30", convert it to a proper time value first (you can parse with LEFT/MID/FIND and feed into TIME). For totals over 24 hours, use a display format like [h]:mm so hours don't wrap.
Google Sheets: copy-friendly time to decimal conversion
Sheets uses the same day-fraction idea as Excel. If A1 is a proper time value:
- Convert to hours:
=A1*24 - With rounding:
=ROUND(A1*24, 2) - By parts:
=HOUR(A1)+MINUTE(A1)/60+SECOND(A1)/3600
If A1 is text, rebuild a time using TIME before multiplying by 24 so your math behaves as expected.
Where time to decimal conversion helps
- Payroll and timesheets: Add decimal hours fast and multiply by rates without manual conversions. Decimal time conversion streamlines payroll processing.
- Project tracking and billing: Log time in a single unit, create cleaner invoice lines, and analyze utilization with time conversion to decimal methods.
- Field service and logistics: Compare shift lengths and travel times on a simple scale using decimal time conversion.
Common time to decimal conversion mistakes (easy fixes)
- Using text like time: A cell with "7:30" as plain text won't calculate. Convert it to a real time value first.
- Mixing units: Minutes must be divided by 60, seconds by 3600—then add to hours.
- Double rounding: Rounding each line and the total can skew results. Decide where you'll round and keep it consistent.
- 24-hour wrap: If totals exceed 24h, use
[h]:mmto display so durations don't reset. - Locale decimals: Dots vs commas matter. Check separators in pasted data and CSV exports.
Quick reference for time to decimal conversion
| HH:MM | Decimal hours |
|---|---|
| 6:00 | 6.00 |
| 6:15 | 6.25 |
| 6:30 | 6.50 |
| 6:45 | 6.75 |
| 7:05 | 7.08 |
| 7:30 | 7.50 |
| 8:45 | 8.75 |
Want a longer table? Generate it with h + m/60 at the minute steps you use most.
FAQ about time to decimal conversion
Is time to decimal conversion the same as historical decimal-time systems?
No. We keep the 24-hour day and convert standard clock time to decimal hours for calculation. That's different from 10-hours-per-day systems.
What rounding is best for payroll time to decimal conversion?
Two-decimal rounding (0.01 hour) is common. Some teams need increments like 0.25 hour. Follow your policy and keep it consistent.
How should I handle seconds in time to decimal conversion?
Include seconds as s/3600, or round at the minute or hundredth-hour if seconds don't affect your outcome.
Prefer not to calculate by hand? Our time to decimal conversion calculator converts instantly and lets you copy the result straight into your timesheet or invoice.