Calculator

Contribution Margin Calculator

Calculate what each order contributes after variable costs like COGS, fulfillment, fees, ads, and returns.

Inputs

Enter the per-order assumptions you want to audit. Defaults use a realistic single-SKU example.

Results

Order economics summary

All outputs update immediately as assumptions change.

Gross revenue

$68.00

Net revenue

$61.20

Contribution profit

$29.91

Profit after ad spend

$15.91

Output summary

Use this table to inspect the commercial outcome before fixed overhead.

Gross revenue$68.00
Net revenue$61.20
Total variable costs$45.29
Contribution profit$29.91
Contribution margin percent26.0%
Profit after ad spend$15.91

Cost breakdown by category

Expected returns cost is rate-based. The rest are modeled as per-order costs.

COGS $18.00
Inbound freight $1.80
Packaging $1.25
Fulfillment $5.95
Payment fees $2.07
Platform fees $0.00
Returns allowance $0.72
Ad spend $14.00
Other variable cost $1.50

How it works

  • Contribution margin extends past gross margin to include the costs that move with the order.
  • Relevant variable costs usually include product cost, fulfillment, transaction fees, returns allowance, and ad spend.
  • Returns and ad spend materially change what an order contributes, even when gross margin looks acceptable.
  • This calculator stops before fixed overhead such as salaries, rent, and software.

Common mistakes

  • Ignoring returns because they do not hit every single order.
  • Excluding payment fees or platform fees from the order model.
  • Mixing fixed overhead into per-order variable economics.
  • Using gross margin as a proxy for contribution margin.