Break-even: how many units it actually takes to cover costs

Break-even isn't a guess about how a launch will go — it's one division. Fixed costs divided by how much each sale actually contributes toward them, after covering what that sale cost to make. Once you know those three numbers, you know the number.

The formula

Units to break even = fixed costs ÷ (price per unit − cost per unit). The bottom of that fraction is your contribution margin — what's left from each sale after the variable cost of making it, before it starts paying down the fixed costs that don't change with volume (rent, salaries, equipment).

A real example: a $9,000 fixed cost, sold at $50

A small workshop has $9,000 a year in fixed costs (rent, insurance, a shared tool). Each unit sells for $50 and costs $20 to make.

1. Contribution margin: 50 − 20 = $30 per unit.
2. Break-even: 9,000 ÷ 30 = 300 units.
3. Revenue at that point: 300 × 50 = $15,000.

Check it: $15,000 in revenue, minus 300 × $20 = $6,000 in variable cost, minus $9,000 fixed — exactly $0 profit. 300 units is genuinely the break-even point, not just the fixed-cost number restated. Sell 301 and the $30 of margin on that extra unit is the first dollar of actual profit.

A real example: the same shop, a $10 price increase

Same $9,000 fixed costs, same $20 cost to make, but the price moves from $50 to $60.

1. Contribution margin: 60 − 20 = $40 per unit.
2. Break-even: 9,000 ÷ 40 = 225 units.
3. Revenue at that point: 225 × 60 = $13,500.

A 20% price increase (from $50 to $60) cut the break-even point from 300 units to 225 — 75 fewer units needed, a 25% drop. Small margin changes near the bottom of the fraction move the units figure by more than the same-sized change to price alone would suggest, because that $10 is pure margin, not diluted by the cost that stays fixed.

A real example: what a thin margin actually costs in volume

Same $9,000 fixed costs and $20 cost to make, but this time priced at just $22 — a thin, competitive margin.

1. Contribution margin: 22 − 20 = $2 per unit.
2. Break-even: 9,000 ÷ 2 = 4,500 units.
3. Revenue at that point: 4,500 × 22 = $99,000.

Cutting the margin from $30 down to $2 — a 93% drop — doesn't shrink the break-even point proportionally, it multiplies it: 300 units becomes 4,500, fifteen times as many. A thin margin doesn't just mean less profit per sale, it means needing a dramatically larger market just to reach zero.

What this doesn't capture

This treats price and variable cost as constant no matter how many units sell, which real businesses rarely get for free — selling more can mean discounting, and making more can mean bulk savings or added shipping and labor. It also ignores taxes, financing costs and the time value of the fixed costs you're paying before the first sale. Treat it as the honest floor, not the whole plan.

Run your own numbers

The free Break-Even calculator runs this instantly for your own fixed costs, price and cost per unit — entirely on your device.