ROAS vs ROI: What’s the Difference and Which One Should You Use?

ROAS and ROI answer different questions. Return on ad spend asks how much attributed revenue an advertising dollar generated. Return on investment asks what profit remained relative to an explicitly defined investment. A campaign can therefore report an attractive ROAS and still lose money. Start with the ROAS calculator for the revenue-to-ad-spend ratio, then inspect the costs behind that number before deciding whether to scale.

ROAS measures attributed revenue per advertising dollar

The formula is ROAS = attributed revenue ÷ ad spend. Spend $1,000 and attribute $3,000 in sales to the campaign, and ROAS is 3.0x, or 300% when expressed as a percentage. The multiple is usually clearer: every dollar spent on ads is associated with three dollars of reported revenue. This is a useful media efficiency signal when campaigns use the same conversion value settings, attribution method, currency and time window.

ROAS by itself does not subtract product cost, payment fees, packaging, variable shipping, discounts or returns. It also cannot prove that every attributed sale was caused by the ad. A dashboard may credit an order that would have occurred organically. For a practical comparison, reconcile attributed order value with net sales after returns and document your measurement assumptions. Google Ads defines ROAS in its official glossary as conversion value divided by cost; your profitability worksheet must add the business costs the ad metric omits.

ROI measures profit against a defined investment

ROI is less standardized in marketing conversations because people choose different costs and investment bases. For the examples in this guide, we use a campaign-level variable-cost ROI: (net revenue − non-ad variable costs − ad spend) ÷ (non-ad variable costs + ad spend). The numerator is contribution profit after advertising. The denominator includes the product and delivery costs plus media spend used to generate those orders. This definition is explicit so you can reproduce it; an organization that includes salaries, software, agency fees or capital investment in its denominator will calculate a different ROI.

Do not mix this campaign-level ROI with company-wide net profit, and do not call revenue minus ad spend “profit” when merchandise and fulfillment costs still need to be paid. Use the profit margin calculator to check the distinction between margin and markup, then calculate contribution margin using the actual variable costs relevant to an additional order.

Save the exact revenue basis, cost categories and reporting dates beside the result so the next review is comparable. The free ROAS profitability workbook gives you a reusable place to document those assumptions and translate the result into CPA and CPC guardrails.

A worked example with both metrics

Suppose a campaign produces $35,000 of net attributed sales in the same period as $10,000 of media spend. Merchandise, payment processing, packaging and variable fulfillment total $18,000. ROAS is $35,000 ÷ $10,000 = 3.5x. Profit after these specified variable costs and ads is $35,000 − $18,000 − $10,000 = $7,000. Under the ROI convention above, investment is $18,000 + $10,000 = $28,000, so campaign-level ROI is $7,000 ÷ $28,000 = 25%.

The $7,000 is not necessarily company net profit. Fixed rent, staff salaries, software and other overhead have not been allocated in this example. If management wants fully loaded ROI, it must define and add those costs consistently for each campaign. Conversely, for a short-term marginal spend decision, some fixed overhead will not change when you buy one more ad impression. State the decision before choosing a cost basis.

The same 3x ROAS can mean profit or loss

Compare two products that each generate $3,000 of net attributed revenue from $1,000 of ad spend. Product A has a 60% contribution margin before ads after merchandise and other variable costs. Its pre-ad contribution is $3,000 × 0.60 = $1,800; subtract ads and $800 remains. Product B has a 25% pre-ad contribution margin. Its pre-ad contribution is only $750; after ads it loses $250. Both show 3.0x ROAS, but their economics point in opposite directions. Product B is below break-even rather than merely close to it.

Assuming the margin and ROAS use the same net revenue basis, break-even ROAS = 1 ÷ pre-ad contribution margin. Product A needs 1 ÷ 0.60 = 1.67x, rounded, and Product B needs 1 ÷ 0.25 = 4.0x. At exactly the threshold, contribution after ads is zero before fixed overhead. A target above it can provide a profit cushion, but a higher target may reduce volume; compare total contribution dollars as well as ratio changes. Enter your own unit economics into the break-even ROAS calculator instead of borrowing a generic “good ROAS” benchmark.

What should count as revenue and cost?

Use net revenue from the same set of orders and the same date window as media spend. Decide whether shipping charged to customers and sales tax are included in platform conversion value; avoid counting pass-through tax as earned revenue. Subtract refunds, cancellations and discounts in a consistent manner. If a return occurs after the reporting window, revisit the cohort once it matures. Google Ads notes that conversion data can arrive with a reporting delay, so an immature campaign may look different from a settled one.

Variable costs can include cost of goods sold, pick-and-pack, payment fees, freight subsidies, marketplace fees and return handling when attributable. Agency fees, salaries and tools may be relevant for a fully loaded ROI but do not silently include them in one campaign and omit them in another. For subscriptions or repeat purchases, specify whether you are measuring first-order economics or a longer customer cohort. Expected future value is uncertain until retention, collection and service costs are measured.

Use the right metric for the next decision

For creative and audience comparisons, ROAS can reveal how much reported revenue was generated per advertising dollar. For budget approval, product prioritization or expansion, contribution profit and a documented ROI definition give a stronger answer. A campaign with lower ROAS can create more total profit if it brings in substantially more sales above its break-even point. Before reallocating spend, compare the incremental revenue and variable contribution from the next tranche of budget with its incremental ad cost, not just historical averages.

If you are evaluating tactical changes, the guide to improving ROAS walks through measurement, conversion rate, average order value and marginal profit tests. For a planned profit cushion rather than mere break-even, see the target ROAS formula. These steps link the dashboard metric to the decision the business actually needs to make.

A reporting worksheet you can repeat

1. Choose the campaign, attribution settings, currency and comparable date range. Export spend and attributed revenue.
2. Reconcile order value with net revenue, returns, canceled orders and any tax or shipping treatment.
3. List non-ad variable costs for the same orders; calculate pre-ad contribution margin as (net revenue − non-ad variable costs) ÷ net revenue.
4. Calculate ROAS, break-even ROAS, contribution profit after ads and ROI using a written denominator.
5. Compare both total profit and marginal results before raising or cutting spend; revisit the figures as delayed conversions and returns settle.

This worksheet is a decision aid, not a causal measurement experiment. Attribution rules can shift credit among channels without changing total sales. When the decision is large enough, a controlled holdout or other incrementality method can help estimate whether additional advertising caused additional demand.

Frequently asked questions