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Profit For Sellers

Advertising

Paid traffic only helps if contribution after product costs, fees, fulfillment, and refunds can still cover acquisition cost. These tools help you judge that from unit economics. They do not connect to ads managers or import live campaign data.

CPA vs ROAS vs ACoS

CPA (cost per acquisition) is advertising spend per order. ROAS (return on ad spend) is revenue divided by advertising spend. ACoS (advertising cost of sales) is advertising spend divided by revenue—the inverse view of ROAS when both are defined on the same revenue base.

Revenue ROAS alone does not prove profitability. Two products can report the same ROAS and still leave very different profit if product cost, payment or platform fees, fulfillment, or refund losses differ. What matters for break-even is contribution available before advertising, not revenue by itself.

Contribution before advertising

Pre-ad contribution is what remains of order revenue after non-ad variable costs: product cost, fulfillment or shipping you bear, payment/platform fees, and expected refund or return effects under your assumptions. That contribution is the budget available to pay for customer acquisition before profit turns negative.

Maximum affordable CPA is that pre-ad contribution (at zero desired profit after ads). Break-even ROAS converts the same economics into a revenue-to-ad-spend threshold. Target ROAS raises the bar when you want profit left after ads, not just break-even.

How costs change ad economics

Higher product cost, fees, or fulfillment lowers contribution and tightens maximum CPA. Expected refunds reduce net economics further when you model unsuccessful orders. That is why identical ROAS on two SKUs can still mean one product is profitable and the other is not: the same ad efficiency sits on different cost structures.

Decision workflow

  1. Determine expected revenue per order.
  2. Determine non-ad variable costs (product, fulfillment, fees, and related assumptions).
  3. Calculate pre-ad contribution.
  4. Determine maximum CPA from that contribution.
  5. Convert that into break-even ROAS and, if needed, a target ROAS.
  6. Compare those thresholds to actual advertising performance.

Tools and guides

The dedicated solver is the Break-Even ROAS Calculator. It solves for break-even ROAS, maximum CPA, ACoS, and a target ROAS from unit economics and expected refunds. For the full walkthrough, read Break-Even ROAS: How to Calculate the ROAS You Need to Be Profitable.

If advertising cost per order is already known and you want expected profit, use the E-commerce Profit Calculator. If you need a selling price that still leaves room for acquisition cost and a target margin, use the Product Pricing Calculator. Browse all tools on the calculators hub. For modeled refund, ad-cost, and COGS scenarios, see the e-commerce profit sensitivity analysis.