Commerce definitions

Ecommerce Profit Metrics Glossary

Ecommerce profitability is not a single number. Gross margin, contribution profit, CAC, LTV, refunds, shipping, discounts, payment fees, and inventory costs all answer different operating questions. This glossary defines common ecommerce profit metrics with formulas, aggregation notes, and caveats for comparing storefront, ad platform, finance, and warehouse data.

Profit needs cost rules COGS, shipping, payment fees, fulfillment, discounts, and returns need consistent assignment rules.
Date basis matters Order date, refund date, return received date, and cost effective date can produce different answers.
Percentages need totals Margin, refund rate, CAC, LTV, and ROAS should be recomputed from governed inputs.
Sales and returns

Revenue inputs that shape profit

Profit reporting starts with a clear sales basis. Gross sales, net sales, returns, refunds, and cancellations answer different questions and should not be collapsed into one unlabelled revenue number.

Gross Sales

Total product sales before discounts, refunds, taxes, and shipping adjustments.

FormulaSum of item list price x quantity.
GrainUsually line-item grain; additive over orders and time.
PitfallTreating gross sales as revenue available to the business.
Net SalesDiscountsRefunds

Net Sales

Sales after discounts and returns, excluding pass-through items such as tax.

FormulaGross Sales - Discounts - Returns.
GrainAdditive when return timing is handled consistently.
PitfallMixing order-date sales with refund-date returns without labeling the basis.
Gross SalesRefund Rate

Discounts

Price reductions from promotions, codes, automatic discounts, or markdowns.

FormulaGross Sales - Discounted Sales.
GrainBest tracked at line item or order level.
PitfallCounting discounts twice when both line and order discounts exist.
Net SalesGross Margin

Returns

Value of refunded or returned merchandise.

FormulaSum of refunded product value.
GrainCan be recorded by order date, refund date, or return received date.
PitfallComparing periods without knowing which return date basis is used.
Refund RateNet Sales

Refund Rate

Share of sales refunded.

FormulaRefunds / Gross Sales or Refunds / Net Sales.
GrainDefine denominator and date basis before comparing.
PitfallUsing refund rate without separating partial refunds, cancellations, and returns.
ReturnsNet Sales

Cancellations

Orders canceled before fulfillment or revenue recognition.

FormulaCount or value of canceled orders.
GrainOrder-level metric; usually not equivalent to returns.
PitfallCombining cancellations with post-purchase returns.
OrdersReturns
Costs

Variable costs that should be explicit

Commerce profit changes when costs are missing, allocated differently, or applied with the wrong effective date. Cost rules should say which cost types are included and where each cost belongs.

Cost of Goods Sold

Direct product cost associated with sold items.

FormulaUnit Cost x Quantity Sold.
GrainBest at line-item grain; cost rules must be versioned or dated.
PitfallUsing current product cost for historical orders when costs changed.
Gross ProfitGross Margin

Shipping Revenue

Amount charged to customers for shipping.

FormulaSum of customer shipping charges.
GrainUsually order-level; may need allocation to lines for product analysis.
PitfallAssuming shipping revenue offsets shipping cost one-to-one.
Shipping CostContribution Profit

Shipping Cost

Carrier, label, packaging, or fulfillment shipping expense.

FormulaSum of shipping expense.
GrainUsually order-level; allocation needed for SKU-level profit.
PitfallIgnoring free-shipping subsidies or using estimated rather than actual cost.
Shipping RevenueFulfillment Cost

Fulfillment Cost

Pick, pack, warehouse, handling, and operational costs tied to order fulfillment.

FormulaSum of fulfillment fees or allocated fulfillment cost.
GrainOrder-level or line-level depending on the data source.
PitfallExcluding 3PL fees from contribution profit.
Shipping CostContribution Profit

Payment Processing Fees

Fees charged by payment processors, wallets, or commerce platforms.

FormulaTransaction Amount x Fee Rate + Fixed Fee.
GrainUsually transaction or order-level; refunds may reverse some fees.
PitfallApplying one blended rate to all payment methods without checking variance.
Contribution ProfitNet Sales

Marketplace Fees

Platform commissions, referral fees, or selling fees.

FormulaSales x Commission Rate + Fixed Fees.
GrainOften order-line or SKU-category dependent.
PitfallUsing storefront margin logic for marketplace orders with different fee structures.
Contribution MarginGross Profit

Variable Costs

Costs that vary with orders, items, transactions, or fulfillment activity.

FormulaCOGS + included shipping, fulfillment, payment, marketplace, and handling costs.
GrainShould be allocated to the same grain as the profit metric being reported.
PitfallCalling a metric contribution profit while excluding major variable costs.
Contribution ProfitOrder Profit
Profit

Margin and order economics

Profit metrics should declare which costs are included. Gross profit, contribution profit, and order profit are not interchangeable.

Gross Profit

Profit after product costs, before fulfillment, payment, marketing, and overhead costs.

FormulaNet Sales - COGS.
GrainAdditive at order line or order grain if COGS is allocated correctly.
PitfallTreating gross profit as fully loaded profitability.
COGSGross Margin

Gross Margin %

Gross profit as a percentage of net sales.

FormulaGross Profit / Net Sales.
GrainRatio; aggregate from summed numerator and denominator.
PitfallAveraging daily or product-level margin percentages.
Gross ProfitNet Sales

Contribution Profit

Profit after variable costs such as COGS, shipping, fulfillment, payment fees, and marketplace fees.

FormulaNet Sales - COGS - Variable Costs.
GrainAdditive if all variable costs are assigned to the same grain.
PitfallCalling contribution profit net profit when fixed costs and overhead are excluded.
Gross ProfitContribution Margin

Contribution Margin %

Contribution profit as a percentage of net sales.

FormulaContribution Profit / Net Sales.
GrainRatio; aggregate using summed values, not averaged percentages.
PitfallComparing products without consistent cost inclusion rules.
Contribution ProfitGross Margin

Order Profit

Profit attributable to an order after included costs.

FormulaOrder Net Sales - Order Costs.
GrainOrder-grain metric; line costs may need rollup.
PitfallMixing order profit definitions across teams, especially before and after ad spend.
Order Line ProfitAOV

Order Line Profit

Profit attributable to a specific product line within an order.

FormulaLine Net Sales - Line COGS - Allocated Costs.
GrainLine-item grain; order-level costs need allocation rules.
PitfallAllocating shipping or discounts inconsistently across items.
SKU ProfitOrder Profit

Average Order Value

Average revenue per order.

FormulaNet Sales / Orders.
GrainOrder-grain ratio from summed values.
PitfallOptimizing AOV while lowering profit through discounts or shipping subsidies.
Order ProfitUnits per Order

SKU Profit

Profit generated by a specific SKU.

FormulaSKU Net Sales - SKU Costs.
GrainSKU and time grain; requires careful cost and discount allocation.
PitfallRanking SKUs by revenue instead of profit.
Order Line ProfitGross Margin
Customer economics

Acquisition, LTV, and payback

Customer profitability depends on identity resolution, first-order logic, attribution windows, cost basis, and whether LTV is observed or modeled.

New Customer Revenue

Revenue from customers placing their first order.

FormulaSum of net sales from first-time customers.
GrainCustomer and order grain; depends on identity resolution.
PitfallMisclassifying returning customers when email, phone, or platform IDs differ.
New Customer ProfitCAC

New Customer Profit

Profit from first orders or first-period customer activity.

FormulaNew Customer Net Sales - Included Costs.
GrainDefine whether this is first order only or acquisition cohort period.
PitfallComparing against ad spend without a clear attribution window.
CACPayback Period

Repeat Customer Profit

Profit from customers after their first purchase.

FormulaRepeat Customer Net Sales - Included Costs.
GrainCustomer and order grain; cohort definitions matter.
PitfallTreating repeat profit as incremental without considering discounts or retention costs.
LTVRepeat Purchase Rate

Customer Acquisition Cost

Marketing and sales cost to acquire a new customer.

FormulaAcquisition Spend / New Customers.
GrainPeriod or channel grain; attribution logic must be explicit.
PitfallUsing total customers instead of new customers in the denominator.
New Customer ProfitPayback

Blended CAC

Acquisition cost across all channels or campaigns.

FormulaTotal Acquisition Spend / New Customers.
GrainPeriod-level metric; not channel-attributed.
PitfallUsing blended CAC to judge individual channel efficiency.
CACMER

Profit LTV

Lifetime contribution profit per customer over a defined window.

FormulaCustomer Contribution Profit over a defined window.
GrainCohort or customer grain; can be observed or modeled.
PitfallComparing modeled LTV to observed CAC without labeling confidence and window.
LTVCACPayback

Payback Period

Time needed for customer profit to recover acquisition cost.

FormulaTime until cumulative profit is greater than or equal to CAC.
GrainCohort-based; requires time-series customer profit.
PitfallCalculating payback from revenue instead of profit.
CACProfit LTV
Inventory

Inventory costs and product availability

Inventory metrics often rely on estimates and operational assumptions. They should be labeled as modeled when exact lost demand, carrying cost, or stockout impact is not directly observed.

Inventory Carrying Cost

Cost of holding inventory over time.

FormulaAverage Inventory Value x Carrying Cost Rate.
GrainInventory and time grain; often modeled or estimated.
PitfallIgnoring storage, capital, shrinkage, and obsolescence costs.
Inventory TurnoverStockout Cost

Inventory Turnover

How often inventory sells through during a period.

FormulaCOGS / Average Inventory Value.
GrainPeriod and product grain.
PitfallUsing sales revenue instead of COGS in the numerator.
Carrying CostSell-Through

Sell-Through Rate

Share of available inventory sold during a defined period.

FormulaUnits Sold / Units Available.
GrainProduct, SKU, location, and period grain.
PitfallComparing products with different launch dates or replenishment patterns.
Inventory TurnoverUnits Sold

Stockout Cost

Estimated lost profit from unavailable inventory.

FormulaLost Units x Estimated Profit per Unit.
GrainModeled estimate; not directly observed in most systems.
PitfallPresenting stockout cost as exact without demand assumptions.
Inventory ForecastGross Profit
Commerce modeling

Profit metrics need explicit assumptions

Commerce Intelligence should make cost assumptions visible instead of hiding them inside a dashboard total.

Separate revenue from profit

ROAS, MER, and sales growth can improve while contribution profit declines. Keep revenue, cost, and profit fields visible.

Use dated cost rules

Product costs, payment rates, shipping fees, and marketplace fees change. Historical orders should use the rule that applied at the time.

Label modeled metrics

Stockout cost, forecasted demand, modeled LTV, and attributed profit require assumptions. Label them differently from observed transactions.

FAQ

Ecommerce profit questions

The common reporting failures are missing costs, mismatched timing, unclear attribution, and averaged percentages.

What is the difference between gross profit and contribution profit?

Gross profit subtracts product cost from revenue. Contribution profit subtracts additional variable costs such as shipping, fulfillment, payment fees, and marketplace fees.

Why can revenue increase while profit decreases?

Discounts, higher shipping cost, lower product margin, returns, payment fees, or inefficient acquisition spend can reduce profit even when sales grow.

Should CAC be compared to revenue or profit?

For payback and sustainability, CAC should usually be compared to gross profit or contribution profit, not only revenue.

Is ROAS the same as profitability?

No. ROAS is attributed revenue divided by ad spend. Profitability depends on product cost, discounts, returns, shipping, fees, and other included costs.

How should shipping costs be allocated?

For order profit, shipping can stay at order grain. For SKU or product profit, shipping needs a documented allocation rule, such as by weight, revenue share, or item count.

Why should margin percentages be recomputed?

Margin percentages are ratios. Aggregated margin should use summed profit divided by summed revenue, not an average of row-level margins.

Need general marketing definitions too?

Use the marketing metrics glossary for spend, impressions, clicks, CTR, CPC, CPA, ROAS, MER, CAC, retention, LTV, and aggregation caveats.

Open marketing glossary