With the illustrative inputs below, the result is 52 sales per month.
Try this with your own numbersFormula and worked example
Capacity = staff × hours × utilization / hours per sale
| Input | Example |
|---|---|
| Delivery staff | 4 |
| Available hours per staff member | 160 |
| Billable utilization | 65 % |
| Hours per appointment | 8 |
| Calculated result | 52 sales per month |
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 is headcount alone not enough to predict capacity?
Availability, nonbillable time, and hours required per sale determine the delivery throughput.
Assumes interchangeable skills and a stable average job duration.
What if this input changes?
If delivery staff rises by 10%, this example changes by 5.2 sales per month. 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.