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Free ecommerce calculators
Calculate contribution margin, break-even ROAS and channel profit for one product in seconds. Nothing you enter is stored.
Contribution Margin Calculator What you actually keep from each sale
How it's calculated and FAQ →Contribution margin is revenue minus every cost that comes with each order: product cost, marketplace and payment fees, shipping, packaging, returns and ad spend. It has to be positive before you can cover fixed costs.
Custom fees
Enter your own channel and payment fees. Defaults are reference values from public pages as of November 2026.
Ad spend
Contribution per unit
$3.18
Margin 8.2% · before ads $16.18
Break-even ROAS
241%
ROAS to keep 10%
318%
Monthly contribution
$954.00
Monthly ad spend
$3,900.00
Where $39.00 of revenue goes
COGS
$11.00
Fees
$3.90
Shipping
$6.50
Pack & returns
$1.42
Ads
$13.00
Contribution
$3.18
Run this for every SKU and channel, daily
Connect orders, ad spend and product costs, and Laplace calculates contribution margin and real ROAS for every product every day, including bundle and gift costs.