Return on Ad Spend Calculator

Enter ad spend and revenue attributed to that spend. The tool returns ROAS as a ratio (revenue ÷ spend) and as a percentage. Add a margin field and it returns a profit-adjusted ROAS, which is what actually matters once costs are included.

Use it per channel, per campaign, or per ad group. A blended ROAS across all your spend hides which campaigns are pulling weight and which are bleeding. Break it down to the level you can actually act on.

ROAS isn't profit. A 2× ROAS at 30% gross margin is a loss when you also pay for fulfillment, returns, and overhead. The calculator shows both top-line ROAS and a margin-adjusted figure for that reason.

ROAS = revenue attributed to ad spend ÷ ad spend. ROAS percentage = ROAS × 100%. A 4.0 ROAS (or 400%) means $4 of revenue per $1 of spend. The metric ignores costs other than the ad spend, which is why a high ROAS doesn't necessarily mean profitable spend — a 3x ROAS at 25% gross margin loses money on every customer the ad acquired. The calculator's profit-adjusted mode applies a margin input and returns net contribution per dollar of spend.

Worked example. Campaign spend: $5,000. Attributed revenue: $20,000. ROAS = 4.0 (or 400%). Looks great. Apply 30% gross margin: gross profit per dollar = $4 × 0.30 = $1.20 contribution after spend. Subtract the $1 spend: net $0.20 per dollar of spend, or 20% net contribution. The same campaign at 60% gross margin produces $4 × 0.60 = $2.40 contribution per dollar spend, $1.40 net — much healthier. The headline ROAS hides the margin difference completely.

ROAS as a target varies wildly by business model. Direct-to-consumer brands often need 4-6x ROAS to net profit. Subscription businesses can run lower (1-2x first-month ROAS) because LTV extends beyond the initial transaction. Lead-gen businesses need much higher ROAS on a per-lead basis because lead-to-customer conversion adds another funnel step. Don't compare your ROAS against "industry averages" — the variance within industries dwarfs the cross-industry mean.

Attribution is the silent killer. ROAS depends on which conversions you attribute to the campaign. Last-click attribution overweights bottom-funnel campaigns; first-click overweights brand awareness; multi-touch is fairer but harder to compute. Apple's ATT changes (2021) and the deprecation of third-party cookies have made cross-platform attribution dramatically harder; observed ROAS today is much lower than equivalent campaigns measured in 2019, even when underlying performance is identical. The calculator works on whatever attribution number you supply — garbage in, garbage out.

A contrarian opinion: stop optimizing for ROAS in isolation. The right metric is incremental ROAS (the lift over what you'd have earned without the spend), and that requires real holdout testing. Most campaigns measure observed ROAS, attribute it all to spend, and overestimate ad-driven revenue by 20-50%. Run quarterly geographic holdouts to estimate the true incremental impact, then size budgets to that — not to last-click ROAS.