Methodology
How the Ecommerce Profit Engine models product economics, marketplace fees, contribution profit and break-even.
Calculation framework
At its core, the engine models retained product revenue and subtracts marketplace-specific fees plus product and operating costs. Marketplace rules remain isolated in adapters so one platform's methodology does not contaminate another.
Break-even
The production calculator evaluates the profit function to estimate the selling price at which modeled contribution reaches zero under the entered assumptions. Because fee structures can contain fixed, variable and tiered components, marketplace-specific rules should be kept explicit rather than reduced to one universal percentage.
Marketplace assumptions
Rates can vary by country, category, seller plan, fulfillment program and promotional program. Users should verify current official marketplace terms before relying on a commercial decision.
What the model is for
The tool is designed for product-level planning, pricing, channel comparison and scenario analysis. It is not a substitute for accounting records, tax calculations, legal advice or marketplace invoices.
Review boundaries
Mathematical correctness, marketplace fee accuracy and live-site behavior are reviewed as separate QA layers. This prevents a current fee schedule from being confused with a permanent formula assumption.