With the illustrative inputs below, the result is 515.242 .
Try this with your own numbersFormula and worked example
Charge = (required receipt + fixed fee) / (1 − percentage fee)
| Input | Example |
|---|---|
| Required net receipt | 500 |
| Processor fee | 2.9 % |
| Fixed transaction fee | 0.3 |
| Calculated result | 515.242 |
Choose reliable inputs
Allow time for preparation, the service itself and cleaning up before the next appointment. For this optometry practice calculation, use appointment history, service durations and supply costs and a consistent definition of one appointment.
- Staff time: include the portion belonging to this appointment or reporting period, and record where the value came from.
- Equipment: include the portion belonging to this appointment or reporting period, and record where the value came from.
- Admin work: include the portion belonging to this appointment or reporting period, and record where the value came from.
Use the same currency for every money input. Do not mix weekly costs with monthly revenue, or count the same expense in both an itemised cost and allocated overhead.
Why does adding the fee percentage leave a shortfall?
The percentage fee applies to the final charge. This arithmetic does not determine whether surcharging is permitted.
What if this input changes?
If required net receipt rises by 10%, this example changes by 51.4933 . This shows the effect of one change; it does not predict what will happen.
Open the calculator, save your baseline, then change the input supported by the least reliable estimate in your records. Compare both scenarios before committing to a price or capacity promise.