# Order economics calculator: content and implementation guide

## Customer-facing introduction

See what remains from an order after your selected costs. Enter a representative order, then compare scenarios. The result is modeled contribution, not final business profit or a prediction of future sales.

## Input labels and helper copy

| Code field | Label | Helper text |
|---|---|---|
| netMerchandiseRevenue | Net merchandise revenue | After discounts and expected merchandise refunds; exclude taxes and shipping collected. |
| productCost | Product cost | Use your consistent landed product-cost definition. |
| fulfillmentAndPackaging | Fulfillment and packaging | Include costs not already in product cost or shipping. |
| netShippingSubsidy | Net shipping cost | Shipping cost minus shipping collected from the customer. This can be negative. |
| paymentFees | Payment fees | Enter the actual or estimated dollar fee on the transaction's applicable payment total. |
| otherVariableCosts | Other variable costs | Marketplace fees, variable commissions, return handling, and other costs not already counted. |
| acquisitionCost | Acquisition allocated to this order | Keep its scope consistent with the revenue. This is not automatically fully loaded new-customer CAC. |
| overheadAllocation | Desired overhead contribution | A planning allocation, not another product cost. |
| desiredProfit | Desired profit after this allocation | A planning target; broader business costs and taxes may remain. |

All inputs share one currency. Blank is missing, not zero. All must be finite numbers. Only net shipping cost may be negative. Explicit zero is valid. Store decimal precision and format money for display without rounding intermediate formulas.

## Result labels

- Total included variable costs before acquisition.
- Contribution before acquisition.
- Contribution margin before acquisition.
- Contribution after acquisition, before fixed overhead.
- Break-even ROAS before fixed overhead.
- Allowable acquisition cost at your overhead and profit target.
- Modeled revenue-to-acquisition ratio at that target.

If merchandise revenue is zero, show “Enter positive revenue to calculate ratios.” If contribution is zero or negative, show “Current unit economics do not support positive acquisition spending.” If the target leaves no acquisition allowance, show “Your overhead and profit target leaves no room for paid acquisition under these assumptions.” Do not display Infinity, NaN, or a misleading zero ROAS.

## Reference scenario

Revenue $60; product $24; fulfillment/packaging $3; net shipping subsidy $5; payment fees $2; other variable costs $4; acquisition $15; overhead target $6; desired profit $4.

Expected results: variable costs $38; contribution before acquisition $22; margin 36.6667%; contribution after acquisition $7; break-even ratio 2.72727×; allowable acquisition $12; modeled target ratio 5×.

## User reminders

Do not deduct refunds twice. Do not subtract an overhead allocation per order and then subtract the same full overhead again in the monthly total. Keep the revenue scope aligned with the spending scope. Estimates should be compared with actual orders and a higher-cost scenario.

## Technical reference

`implementation/content-engine.mjs` exports `calculateOrderEconomics(input)`, `assessStore(answers)`, and `scoreProduct(scores, gatesPassed)`. These pure functions perform no network requests or data storage. The calculator is a ready-to-use logic module; the package does not include a deployed calculator interface.

`node implementation/verify-content.mjs` verifies reference calculations, invalid inputs, nonpositive contribution, negative net shipping subsidy, assessment precedence, all allowed assessment combinations, content IDs, and related links.