What it calculates

Break-even analysis finds the sales volume at which total revenue exactly covers total cost, so profit is zero. Everything above that point contributes to profit at the contribution margin rate, which makes it the fastest way to see how much cushion a business has.

How it is calculated

Split costs into fixed, which do not vary with volume, and variable, which do. Contribution margin per unit is price less variable cost per unit - the amount each sale contributes toward covering fixed costs. Break-even in units is fixed costs divided by that contribution margin; in revenue it is fixed costs divided by the contribution margin ratio. The margin of safety is how far current volume sits above break-even, expressed as a percentage.

How to read the result

The contribution margin ratio tells you the operating leverage: a high ratio means profit rises sharply once you clear break-even, and falls just as sharply below it. A thin margin of safety means small volume shocks produce losses, which is why capital-intensive businesses with high fixed costs are so sensitive to utilisation. Compare break-even to realistic capacity - if it sits near the top of what you can produce, the model does not work regardless of demand.

Worked example

Fixed costs of 500,000, a price of 80 and variable cost of 50 give a contribution margin of 30 per unit, a 37.5% ratio. Break-even is 500,000 / 30 = 16,667 units, or 1,333,333 in revenue. At current sales of 22,000 units the margin of safety is 24%.

Common questions

How should semi-variable costs be treated?

Split them into their fixed and variable components, typically with the high-low method or a regression on historical volumes. Treating a semi-variable cost as wholly fixed overstates break-even; treating it as wholly variable understates it.

Does break-even work with multiple products?

Yes, using a weighted-average contribution margin based on the expected sales mix. The result is only valid while that mix holds - a shift toward lower-margin products raises break-even without any change in price or cost.

What is the difference between contribution margin and gross margin?

Gross margin subtracts cost of goods sold, which usually contains some fixed manufacturing overhead. Contribution margin subtracts only genuinely variable costs, wherever they sit in the P&L, including variable selling costs below the gross margin line.