With the illustrative inputs below, the result is 100 %.
Try this with your own numbersFormula and worked example
ROI = (revenue × contribution margin − marketing cost) / marketing cost × 100
| Input | Example |
|---|---|
| Attributed revenue | 15,000 |
| Pre-marketing contribution margin | 40 % |
| Marketing cost | 3,000 |
| Calculated result | 100 % |
Choose reliable inputs
Separate parts, technician time and bay availability for each repair order. For this auto detailing calculation, use repair orders, parts invoices and technician time logs and a consistent definition of one detail package.
- Consumables: include the portion belonging to this detail package or reporting period, and record where the value came from.
- Technician hours: include the portion belonging to this detail package or reporting period, and record where the value came from.
- Bay occupancy: include the portion belonging to this detail package 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.
How is marketing ROI different from ROAS?
ROAS divides revenue by advertising spend. This model subtracts variable delivery costs and marketing spend before calculating return.
Attribution is an input assumption; revenue is not the same as profit.
What if this input changes?
If attributed revenue rises by 10%, this example changes by 20 %. 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.