Quick answer
Return on Ad Spend is calculated as:
Revenue from Ads / Ad SpendUse this Excel version when your inputs are on row 2:
=IFERROR(B2 / C2,0)What is Return on Ad Spend?
Return on Ad Spend measures the cost connected to a business result. It helps show whether the result is efficient enough to justify the money spent.
Marketing KPIs connect campaigns, traffic, leads, customers, and revenue so you can see what actually produces results.
Real-life example
Imagine a marketing manager comparing channels at month end. The team adds the inputs for Return on Ad Spend to a campaign performance dashboard, calculates the KPI for the current month, and compares it with the previous month and target. In the sample below, the result is 400.0%. That number becomes useful when everyone uses the same formula each month.
| Excel cell | Input | What it means | Sample value |
|---|---|---|---|
| B2 | Revenue from Ads | money earned before or after the relevant adjustment, depending on the KPI definition | $48,000 |
| C2 | Ad Spend | the cost included in the calculation for the same period as the output | $12,000 |
| Result | Return on Ad Spend | Output of the KPI formula | 400.0% |
How to calculate Return on Ad Spend in Excel
- Create one row per reporting period, team, product, campaign, location, or customer segment.
- Add one input per column. Do not combine inputs in the same cell.
- Paste the Excel formula in the KPI result column.
- Format the result as Percentage.
- Copy the formula down the table and compare the result against target, previous period, and trend.
- Use the same date range for every input.
- Confirm that the denominator is not blank or zero.
- Document whether the KPI is calculated before or after discounts, refunds, taxes, returns, or cancellations.
- Keep the definition stable so reports remain comparable over time.
Power BI DAX measure
If you also report this KPI in Power BI, create a measure instead of hard-coding the calculation in a visual. Replace the measure names below with the names used in your model.
Return on Ad Spend = DIVIDE([Revenue from Ads], [Ad Spend], 0)For best results, build base measures first, such as revenue, cost, customers, orders, or tickets, and then build the KPI measure from those base measures.
How to read the result
Higher is usually better, because this KPI normally represents revenue, efficiency, quality, retention, productivity, or successful outcomes.
Do not read the KPI alone. A single value can be misleading without a target, trend, segment, and business context. For example, the same result may be good for one product line but poor for another.
Useful comparisons
- Current month versus previous month.
- Actual result versus target or budget.
- By channel, product, customer segment, team, or location.
- Rolling average over several periods to smooth one-off spikes.
Common mistakes
- Mixing time periods, such as monthly cost with quarterly revenue.
- Using a total when the KPI should be segmented.
- Changing the formula definition after the dashboard is already in use.
- Comparing two teams that collect the inputs differently.
- Ignoring blanks, zeros, refunds, cancellations, or duplicate records.