ACoS / ROAS Calculator

Know your current ad performance and your break-even thresholds — the ACoS/ROAS at which you stop losing money. Supports Amazon (ACoS) and Shopify/DTC (ROAS). Manual input, all local.

Ad Spend ($)

Ad-Driven Sales ($)

Gross Margin (%)

Results

Current ACoS (%)

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Current ROAS (x)

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Break-Even ACoS (%)

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Break-Even ROAS (x)

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Est. Ad Profit ($)

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Revenue Breakdown

Chart will render here (IDE)

Scenario Simulation

See how changes affect your result (logic to be implemented by IDE):

Ad Spend Change (%)

Margin Change (%)

Scenario results will be shown here.

What Is ACoS and ROAS?

ACoS (Amazon) = ad spend ÷ ad-driven sales × 100. ROAS (Shopify/DTC) = ad-driven sales ÷ ad spend. They are reciprocals of each other: ACoS 25% = ROAS 4x.

Break-Even ACoS / ROAS — The Number That Matters

Your break-even threshold is the ACoS/ROAS at which ad profit is zero, derived from your true gross margin after refunds, commissions and fees. Above break-even ACoS (or below break-even ROAS), every ad dollar loses money — regardless of what the ad platform reports.

Ad Platform Reported Value vs Net Revenue

Meta/Amazon report conversion value including tax and shipping. Your actual margin is on net revenue. If you don't adjust, your break-even threshold will be wrong. Use the advanced option to correct for this.

ACoS vs TACoS vs MER

ACoS covers ad-attributed sales only. TACoS includes all sales. MER (marketing efficiency ratio) = total revenue ÷ total marketing cost. Each answers a different question about your funnel.

Frequently Asked Questions

What is a good ACoS? ▾

It depends on your margin. The only number that matters is your break-even ACoS — stay below it to profit, above it to lose money.

What is the difference between ACoS and ROAS? ▾

ACoS is spend ÷ sales (Amazon, lower is better). ROAS is sales ÷ spend (Shopify/DTC, higher is better). They are reciprocal.

Why does my break-even ACoS look different from the ad platform's number? ▾

Platforms report gross conversion value. Your margin is net of refunds, commissions, payment fees and tax. The calculator applies those to find your true threshold.