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Check the economics before you place the order.

Enter your price, product cost and fee assumptions to estimate contribution profit, margin, ROI and the price you break even at. Every number below is one you control — this does not look up Amazon's live fees, and it never asks who you are.

Your assumptions

Contribution profit

$8.50

Per unit, after the fees and costs you entered.

Contribution margin

28.33%

Profit as a share of the selling price.

Cost-based ROI

50.00%

Profit divided by product + fulfillment + other costs. ROI conventions differ; this is the denominator used here.

Break-even price

$20.00

The selling price at which contribution profit reaches zero.

The formulas, in full

  • profit = price × (1 − referral) − cost − fulfillment − other
  • margin = profit ÷ price
  • ROI = profit ÷ (cost + fulfillment + other)
  • break-even = (cost + fulfillment + other) ÷ (1 − referral)

What this leaves out

These are not live Amazon fees — the model uses the assumptions you typed, and a proportional referral fee. It omits category minimum fees, non-linear fees, returns, storage, advertising, taxes and business overhead unless you fold them into “other per-unit costs”. A positive contribution profit does not mean the business is profitable. Check the current applicable fees before you buy.

Stop typing the assumptions in

Inside Apex these numbers come from your own account — your landed costs, your prep and shipping, the fees on your real listings — and they run across a whole supplier catalog instead of one product at a time.

Track these numbers in Apex

See Apex Blue for connected profit reporting, Apex Green for catalog analysis, or what a plan costs.

Questions people ask about this

Are these live Amazon fees?

No. This version calculates from the assumptions you enter. Check the current applicable fees for your category and product size before buying.

Does positive contribution mean my business is profitable?

No. Contribution profit is per unit and before the costs of running a business. Include overhead, returns, taxes, advertising and storage in your wider analysis.

Why is my ROI different elsewhere?

ROI conventions differ. This divides profit by product cost plus fulfillment plus other per-unit costs, and the denominator is printed beside the figure so you can compare like with like.