In Simplicate, you log time in hours and minutes. The time notation hh:mm is used.
When invoicing, the number of hours/minutes is displayed as decimals; for example, 1:30 hours is shown as 1.5 hours.
The number of decimal places shown is up to 2. In the background, however, calculations use 6 decimal places to prevent discrepancies.
Example: 10 minutes are billed at a rate of €100. In decimals this is 0.1666667 hours. This is presented as 0.17 hours. The result is €16.67, namely 0.1666667 × €100.
In the Services tab on the (draft) invoice, you will also see this reflected.
Why six decimal places are used
Six decimal places are deliberately used in the calculation to prevent discrepancies. When you bill 3 × 20 minutes or 6 × 10 minutes, you expect the outcome to add up to exactly 1 hour. However, if only two decimal places were used, the outcome would be 6 × 0.17 = 1.02 hours or 3 × 0.33 = 0.99 hours.
How can I prevent rounding differences?
Working in 15-minute blocks
A practical way to avoid rounding differences is to always record time in 15-minute blocks. Fifteen minutes equals exactly 0.25 hours, which is accurate both in the display and in the underlying calculation (with 6 decimals). This prevents rounding discrepancies such as when repeatedly billing 10 or 20 minutes.
Why this works:
15 minutes = 0.25 hours
No rounding is required in the calculation
Multiple entries add up precisely to whole hours
Example: 4 × 0.25 = 1.00 hours
By working in 15-minute increments, invoicing remains clean and consistent.
Correcting hours
When correcting hours, you can simply use two decimal places. Simplicate ensures logical rounding.
Example: you want to bill 15 minutes instead of 10 minutes. You correct the amount of 0.17 by 0.08 so that the total comes to 0.25. The calculation in this case is: 0.25 × €100 = €25.
In the background, a correction of 0.083333 is applied so that the total comes out to 0.25 hours.
The window in which the correction takes place is shown below:
You will also see this reflected on the invoice:
More information about correcting post-calculation hours can be found on the page: