Find your contribution margin — what each sale contributes toward fixed costs and profit — per unit, as a ratio, and the units needed to break even.
Contribution margin = price − variable cost per unit; the CM ratio is that as a percent of price. Break-even units = fixed costs ÷ contribution margin. Variable costs scale per unit; fixed costs don't. General information only.
Every unit you sell brings in its price but costs something variable to produce. The difference — the contribution margin — is what's left to cover fixed costs and, beyond break-even, to become profit. Divide fixed costs by the per-unit margin and you know exactly how many units clear the line.
Contribution margin = price − variable cost; break-even units = fixed costs ÷ CM
Gross profit subtracts all cost of goods; contribution margin subtracts only the variable portion. It's the number that drives break-even and pricing decisions.
Higher is better — it means more of each sale is available for fixed costs and profit. It varies hugely by industry; compare to your own trend and fixed-cost base.
Related: break-even units calculator · profit margin calculator · gross profit calculator · all free calculators.
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Last reviewed: September 2026. Free to use, no signup — Contribution Margin Calculator by ToolWise Digital.
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