Decimal precision and invoice totals
A displayed decimal can be less precise than the duration it represents. Seven minutes is 0.11666… hours, shown here as 0.12.
At $300 an hour, seven minutes is worth $35. Using the rounded 0.12 hours gives $36. If a timesheet and invoice disagree, the point at which hours are rounded is one thing to check.
Rounding to two decimal places is separate from rounding to a billing increment. Seven minutes rounded up to a six-minute increment becomes 12 minutes, or 0.2 hours. The billable hours calculator compares exact time with 6-, 10- and 15-minute rounding. For the full charts and policy considerations, see billing increments explained.
Decimal hours in Excel and Google Sheets
| Starting value | Formula | Result |
|---|---|---|
Duration in A1, such as 1:45 | =A1*24 | 1.75 hours |
Total minutes in A1, such as 105 | =A1/60 | 1.75 hours |
| Whole hours in A1, minutes in B1 | =A1+B1/60 | Decimal hours |
Decimal hours in A1, such as 1.75 | =A1/24 | Duration: 1:45 |
Format decimal results as numbers. For duration results, use [h]:mm to display totals above 24 hours without wrapping back to zero.
The duration formulas assume the source cell contains a spreadsheet time value. An imported text value that looks like 1:45 may need converting first. Changing the number format changes the display; a ROUND formula changes the value used in later calculations.
Converting decimal hours back to minutes
Multiply decimal hours by 60. For reference, 0.25 hours is 15 minutes, 0.12 hours is 7 minutes 12 seconds, and 1.30 hours is 1 hour 18 minutes.
If the decimal was rounded before export, converting it back cannot recover the original duration exactly. The reverse converter above rounds its result to the nearest second.
