Return on ad spend answers a narrow question: how much attributed revenue did advertising produce relative to media spend?
The formula
ROAS = revenue attributed to ads ÷ advertising spend
A campaign with $50,000 attributed revenue and $10,000 spend has a 5× ROAS. The same result can be shown as 500%, but CalcMotive uses the multiplier because it is common in campaign reporting.
Use the ROAS Calculator to reproduce the example. Currency changes formatting only; revenue and spend must already use the same currency.
Calculate ROAS in five steps
- Choose the campaign, channel or account scope.
- Choose a complete reporting period and allow for conversion delay.
- Export media spend for that exact scope.
- Export the conversion value attributed to the same scope.
- Divide attributed value by spend and record the attribution definition beside the result.
| Input check | Campaign revenue | Ad spend |
|---|---|---|
| Same dates | Required | Required |
| Same campaigns and markets | Required | Required |
| Same currency | Required | Required |
| Refund treatment documented | Required | Not applicable |
| Agency, creative and payroll included | Usually no | Usually no |
ROAS normally uses media spend only. If other marketing costs are included in the denominator, label the metric so it is not compared with platform ROAS as if the definitions match.
Align the inputs
Revenue and spend must cover the same campaigns, markets, currencies and attribution window. A platform may continue assigning conversions after the campaign has stopped, so a same-day export can be incomplete.
Use revenue net of cancellations and refunds when the data is available. Document whether taxes and shipping income are included.
A conversion-delay example
Suppose a campaign spends $2,000 during one week. The first export shows $6,000 attributed revenue, or 3× ROAS. Seven days later, additional delayed conversions raise attributed revenue for that same campaign week to $8,000, or 4×.
The campaign did not spend more. The reporting window matured. Compare cohorts or campaign periods at the same age, such as seven days after the period ends, to avoid treating conversion delay as a performance trend.
Attribution changes the numerator
An attribution model decides how conversion credit is distributed across eligible interactions. Lookback windows, conversion actions and model choice can change reported revenue without changing actual orders.
Record at least:
- platform and report name;
- conversion actions included;
- attribution model and lookback window;
- click-through and view-through treatment;
- new and returning customer scope;
- revenue adjustments for refunds or cancellations.
Platform ROAS can remain useful when its definition is stable. It should not be presented as an independent causal estimate.
Compare ROAS with economics
ROAS ignores product cost and operating expense. Calculate break-even ROAS from gross or contribution margin, then leave an additional buffer for overhead and profit. A campaign above break-even can still have poor cash flow or weak incrementality.
Profit bridge example
Continue with the $50,000 revenue and $10,000 ad-spend example. ROAS is 5×. Assume variable product, fulfillment and payment costs total 55% of revenue.
Contribution before advertising = $50,000 × 45% = $22,500
Contribution after advertising = $22,500 - $10,000 = $12,500
The simplified Break-even ROAS Calculator gives 1 ÷ 45% = 2.22×. Actual ROAS is above that threshold, but the $12,500 still needs to cover fixed marketing and operating costs.
| Actual ROAS vs threshold | What the arithmetic indicates |
|---|---|
| Below threshold | Entered margin does not recover media spend |
| Equal to threshold | Contribution after media is zero |
| Above threshold | Some contribution remains for fixed costs and profit |
Separate revenue quality from ratio quality
A campaign can improve ROAS by serving more existing customers, selling a lower-margin product mix or reducing spend until only the easiest conversions remain. Review total contribution, new-customer volume and scale beside the ratio.
When comparing channels, MER vs ROAS explains why blended revenue can move differently from platform-attributed revenue. ROAS vs ROI separates the media ratio from a broader investment return.
Reporting checklist
- State the platform and attribution window.
- Separate prospecting and remarketing where useful.
- Reconcile platform revenue with store or finance data.
- Compare cohorts over consistent time periods.
- Review ROAS together with CAC, contribution margin and new-customer volume.
Common mistakes
- Dividing spend by revenue, which calculates ACoS rather than ROAS.
- Mixing spend and conversion value from different periods or currencies.
- Comparing fresh campaign data with fully matured historical data.
- Treating attributed revenue as entirely incremental.
- Calling revenue less media spend profit.
- Raising budgets from the ratio alone without checking volume and margin.
ROAS is reliable arithmetic applied to a reporting definition. A useful decision requires the formula, the attribution scope and the economic threshold together.
Sources
- Google Ads: conversion values; Google Ads; accessed Jul 13, 2026
- Google Analytics: attribution models; Google Analytics; accessed Jul 13, 2026
This guide is educational and does not provide financial, accounting, tax or legal advice.