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Break-even calculator

Find how many units you need to sell to cover a fixed cost, like a new cooler, a display fee or a month of rent, and how long it will take.

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A new cooler, a display fee, a month of rent: a cost that doesn't change with sales.
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$
Optional. Used for the time estimate.

How break-even works

Every unit you sell brings in a little more than it cost you. That leftover amount, the difference between the selling price and your cost per unit, is what chips away at a fixed cost. Break-even is the point where all those small amounts add up to the full fixed cost.

Profit per unit = Selling price − Cost per unit
Break-even units = Fixed cost ÷ Profit per unit rounded up to a whole unit
Time to break even = Break-even units ÷ Units sold per day, week or month

Economists call the profit per unit the contribution, because it's what each sale contributes toward fixed costs. As a percentage of the price, it's the contribution margin.

Example. A display setup costs $600. The item sells for $3.49 and costs you $2.10, so each sale contributes $1.39.

$600 ÷ $1.39 = 431.7, so you need to sell 432 units, about $1,508 in sales, before the display has paid for itself.

At 40 units a week, that takes about 10.8 weeks. Everything after that is profit.

Good questions to run through it

What the number leaves out

Break-even assumes your price and cost stay the same the whole time, which is fine for a quick decision but not for a long one. It also can't see cannibalization: if a new item mostly takes sales from something you already carry, the real gain is smaller than the units suggest. When that's likely, use only the profit from customers who wouldn't have bought something else.

If the time to break even is longer than the equipment will last or the promotion will run, the numbers are telling you no.

Common questions

What counts as a fixed cost?
Anything that doesn't change with how many units you sell: equipment, fees, rent, insurance, a flat monthly service charge. Costs that rise with each sale, like the product itself or a card processing fee, belong in the cost per unit instead.
Should I include rent?
Only if you're looking at the whole store or the decision changes your rent. For a single new item or a piece of equipment, include only the costs that decision actually adds.
How do I find my cost per unit?
If you buy by the case, the case cost calculator breaks the invoice down to a per-unit cost, freight and discounts included.

Last updated October 11, 2026.