Contribution margin shows how much revenue remains after the variable costs needed to sell and fulfill an order. For ecommerce teams, the useful version depends on cost inclusion rules, order and order-line grain, allocation assumptions, and whether acquisition spend is part of the question.
Gross profit and contribution profit answer related but different questions. Gross profit focuses on product economics. Contribution profit expands the view to variable costs that scale with selling and fulfillment.
Revenue remaining after product cost.
Revenue remaining after selected variable costs.
Gross profit as a share of net sales.
Contribution profit as a share of net sales.
There is no useful contribution margin without cost rules. Each cost should have a source, effective date, allocation method, refund behavior, and grain.
COGS or landed product cost associated with the items sold.
Revenue reductions from promotions, refunds, returns, and cancellations.
Carrier, label, packaging, pick, pack, handling, warehouse, or 3PL costs.
Processor fees, platform commissions, referral fees, and transaction charges.
Acquisition or retention spend used when the question is post-marketing contribution.
Costs intentionally left out of the contribution margin definition.
Contribution margin should be calculated at the lowest reliable grain, then rolled up. When costs exist at a different grain than revenue, allocation rules become part of the metric definition.
Order-level profit is useful for total order economics, customer analysis, and payback. It can keep order-level shipping, fees, and discounts without forcing SKU allocation.
Order-line profit is useful for SKU, bundle, category, and merchandising decisions. It needs line-level revenue and product cost plus allocation for order-level costs.
SKU margin needs stable product identity, dated cost rules, discount allocation, return handling, and enough transaction detail to avoid relying on blended averages.
CAC and payback are more meaningful when compared to profit instead of revenue. The right profit basis depends on whether the question is first-order economics, cohort payback, or lifetime value.
Contribution profit generated by a customer's first order.
Time until cumulative contribution profit recovers acquisition cost.
Observed or modeled contribution profit over a customer lifetime window.
Efficiency ratios that use profit instead of revenue in the numerator.
Contribution margin is a semantic metric. The cost rules, allocation logic, date basis, and grain should be visible and versioned.
Product costs, shipping fees, payment rates, marketplace commissions, and fulfillment costs change. Historical orders should use the rule that applied when the order was created or fulfilled.
When an order-level cost is pushed to order lines or SKUs, name the allocation method. Revenue share, item count, weight, and quantity can produce different results.
Observed fees, actual shipping labels, and transaction costs should be labeled differently from estimated costs, modeled LTV, and forecasted inventory impacts.
Contribution margin reporting is strongest when costs, grain, allocations, and customer timing are explicit.
Contribution margin is contribution profit divided by revenue. Contribution profit is revenue after selected variable costs such as COGS, shipping, fulfillment, payment fees, and marketplace fees.
Gross profit usually subtracts product cost from revenue. Contribution profit subtracts additional variable costs, depending on the cost rules used by the business.
Only when the metric is explicitly post-marketing contribution profit or profit after acquisition spend. Standard contribution margin often excludes ad spend unless defined otherwise.
SKU and product decisions require line-level economics. Order-level discounts, shipping, and fees need documented allocation before they can be used for product-level margin.
CAC should be compared to gross profit or contribution profit when evaluating payback. Revenue alone can overstate how quickly acquisition spend is recovered.
No. Contribution margin usually excludes fixed costs, overhead, financing costs, taxes, and other expenses unless the metric definition says they are included.
Use the contribution-margin calculator to enter one period's revenue, adjustments, variable costs, paid media, and order count without sending the inputs anywhere.