Start with the decision
Break-even in this tool means entered revenue covers entered unit costs and a percentage referral assumption. It does not include every expense your business faces. It also does not choose a price customers will accept.
Worked calculation
With total modeled FBA costs 16.50 and referral assumption 15%, break-even is 16.50 divided by 0.85, approximately 19.4118. A displayed 19.41 is rounded for readability; use at least 19.42 if you need a cent price that clears that mathematical threshold.
Check cent rounding at the break-even threshold
For each fulfillment route, start from the same selling price and subtract the referral assumption, landed product cost and route-specific fulfillment, inbound, storage or dispatch costs. The comparison is only as complete as the inputs; record exclusions alongside the result.
Write the model as a contribution equation before interpreting the answer: price less percentage fees on the applicable base and less entered unit costs. Solve using the same fee base that the marketplace uses, and check whether minimum fees, tiers or taxes make that simple percentage model incomplete. A mathematically exact break-even price can still be commercially unsuitable.
Check the changed-cost scenario
After finding the threshold, test a price above it and include costs omitted from the quick model, such as returns, promotions or operating overhead, in a separate review. Round upward only after the calculation and verify the rounded result by substituting it back into the equation.
| Input or result | Value |
|---|---|
| Entered FBA unit costs | 16.50 |
| Referral assumption | 15% |
| Exact threshold: 16.50 ÷ 0.85 | 19.411764… |
| At 19.41: contribution | −0.0015 |
| At 19.42: contribution | 0.007 |
The tool displays the exact calculation rounded to two decimals. For a cent-priced offer that clears this simplified threshold, round upward and substitute the price back into the equation. Referral minima, tiers and omitted expenses can require a different model.
Use the example with your own inputs
Category fee minima and tiers can change the equation. Check the official estimate rather than assuming one percentage works for every product.
Amazon FBA vs FBM Profit Calculator | PourMarginScope and source checks
These are planning examples, not actual seller results. Keep currency, tax basis and cost allocation consistent. Enter your own figures and reconcile with your records; tax, demand, refunds and unlisted business costs can change the outcome.
Source: Amazon fee and cost estimates. This article uses illustrative manual costs, not current category fee quotes.