How to calculate your break-even point

Break-even is the first number every product owner should know

Before a business asks how much profit a product can make, it has to answer a simpler question: how many units must it sell before the product stops losing money? That number is the break-even point, and getting it wrong is one of the most common reasons new products fail in their first year.

Break-even sits at the intersection of three numbers: fixed costs (the bills you pay no matter how many units you sell), variable cost per unit (what each unit physically costs to produce or deliver), and selling price. Get those three right and the break-even formula is straightforward arithmetic. Get them wrong, and the entire pricing decision rests on faulty assumptions.

Fixed costs versus variable costs

The first job of any break-even calculation is to correctly classify costs.

Fixed costs are the costs that don’t change with sales volume. Rent, salaries, software subscriptions, equipment leases, insurance — these bills arrive whether you sell zero units or ten thousand. Over a single planning period (a month, a quarter, a year), fixed costs are a flat number you have to recover.

Variable costs scale linearly with sales. Raw materials, packaging, payment processing fees, shipping per unit, sales commissions, and any inventory-tied charge — these only happen when a unit moves. Variable costs are a per-unit number.

A common mistake is putting semi-fixed costs (utilities, part-time staff) into the wrong bucket. The rule of thumb: if it scales with units sold, it’s variable. If it would still be paid in a month with zero sales, it’s fixed.

Contribution margin — the heart of break-even

Once costs are classified, the calculation pivots on a single per-unit figure: the contribution margin.

Contribution margin per unit = selling price − variable cost per unit

This is the amount each unit “contributes” toward covering fixed costs. If your selling price is $50 and variable cost is $20, every unit contributes $30 toward fixed costs.

The break-even formula then becomes:

Break-even units = fixed costs ÷ contribution margin per unit

If fixed costs are $30,000 per month and each unit contributes $30, you need 1,000 units to break even — which translates to $50,000 in revenue. Below 1,000 units you lose money. Above 1,000 units, every additional sale is pure profit at a rate of $30 per unit.

Why contribution margin percent matters more than dollar amount

Two products can have the same dollar contribution margin and very different economics. A $30 contribution on a $50 product (60%) is far more resilient than a $30 contribution on a $200 product (15%). Why? Because cost increases and price drops eat margin disproportionately.

A 10% increase in variable cost on the 60%-margin product still leaves a healthy 56% margin. The same 10% increase on the 15%-margin product crushes margin to 11%. Thin margins are fragile margins. A general benchmark: contribution margins under 30% deserve scrutiny; under 10%, they often mean the business is one supplier price increase away from losing money on every sale.

Adding a profit target

Most businesses care about more than just covering costs — they want a target profit on top. Extending the formula:

Units required = (fixed costs + target profit) ÷ contribution margin per unit

If the same business above wanted to earn a $15,000 monthly profit on top of its $30,000 fixed costs, it would need ($30,000 + $15,000) ÷ $30 = 1,500 units. The target-profit calculation turns break-even into a planning tool: it tells you the volume that translates into the income you’re targeting.

When break-even is impossible

If your selling price is at or below your variable cost per unit, break-even is mathematically impossible. Every additional unit makes the loss worse, not better. Some businesses run loss-leaders deliberately (subsidising acquisition through follow-on revenue), but for any standalone product, a non-positive contribution margin is the signal to either raise the price, find cheaper inputs, or kill the product.

Sensitivity is everything

A break-even number is only as accurate as the assumptions behind it. Costs change. Suppliers raise prices. Promotions cut effective selling price. Once you have a baseline break-even, stress-test it by varying each input by 10–20%. If a 10% supplier price increase pushes break-even from 1,000 units to 2,000 units, you know how much margin headroom you actually have.

Use the calculator

Run your own numbers through our break-even calculator to see your break-even point, contribution margin, and target-profit unit count side by side. The calculator also flags thin contribution margins so you know when small input changes will move the break-even point dramatically.