Digital ad platforms show metrics that encourage spending — impressions, clicks, engagement. None tell you whether ads are making money. The metric that matters is ROAS: total revenue divided by ad spend. A 3.0x ROAS means every dollar generates three dollars of revenue.
The Funnel Math
Every campaign is a funnel. You spend money, generate clicks, some clicks become customers, customers generate revenue. Cost per click (CPC) determines reach: $2,000 at $2.50 CPC = 800 clicks. Your conversion rate (typically 2-3% for e-commerce) determines customers: 800 clicks at 2.5% = 20 customers. CPA is $2,000 ÷ 20 = $100 per customer.
If your average order is $75 and CPA is $100, you lose $25 per sale. ROAS is 0.75x — actively burning cash.
The Four Levers
Lower CPC (better targeting, better creative), improve conversion rate (better landing pages, stronger offers), increase average order value (upsells, bundles), or improve margins (reduce costs, raise prices). Small improvements compound across the funnel — the math is multiplicative.
ROAS Targets by Margin
Good ROAS depends on margins. 70% margins can profit at 1.5x ROAS. 30% margins need 3.5x+ just to break even. The formula: minimum ROAS = 1 ÷ profit margin.
See where your campaigns stand with our free Ad Spend ROI Calculator — full funnel visualization from budget to net profit.