Ecommerce profit calculator

The arithmetic, in order: gross = price × (1 - discount) + shipping charged. Net revenue drops the tax when prices include it: net = gross / (1 + tax rate). Returns are expected values: expected net = net × (1 - return rate), and the product cost keeps only the recovered share of returns. Payment and platform fees are charged on gross and are not refunded on returns. Contribution is expected net minus every variable line including ad spend, so break-even ROAS = expected net / contribution on the net basis and gross / contribution on the platform-reported gross basis. Target CPA = contribution - target margin × expected net; a negative figure means no ad spend is affordable at that margin. Monthly profit = contribution × orders - fixed costs, and break-even orders round up. Nothing is rounded until display; money shows two decimals. This is a planning model, not an accountant's ledger: it cannot see warehouse minimums, category fee caps, or tax filing rules.