This break-even calculator tells you how many units of one product you must sell in a period to cover your fixed operating costs, and how many more you need for a target profit. Enter fixed costs for the period, selling price per unit, variable cost per unit and an optional profit target.
The key limit: it assumes one product with a constant price and costs, and it is a cost check, not a sales forecast.
Business break-even calculator
This calculator runs in your browser. This calculator’s code does not send, save, or track your entries. All dollar amounts are USD.
Optional example: Inputs start blank. Load example fills hypothetical figures without calculating. Examples are not current rates, quotes, or recommendations.
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How many units do you need to break even?
For a single product with a positive contribution margin, break-even units = fixed operating costs ÷ (selling price − variable cost per unit). If you sell whole units, round that threshold up.
The SBA’s business-planning guidance gives the same single-product formula. The calculator also shows contribution margin, the operating profit at the rounded threshold and the units needed for a target profit.
Which costs belong in each input?
Choose a period, such as one month, and enter that period’s fixed operating costs. Enter the selling price and variable cost for one unit. Use a target operating profit of 0 if you only need break-even. Expected units are an optional scenario; enter 0 to see the no-sales result.
Fixed costs stay unchanged within the modeled sales range, while variable costs change with each unit sold. Include all per-unit variable operating costs, such as materials, packaging or a sales commission, not just purchase cost.
Split mixed expenses into their fixed and variable parts where you can, and avoid counting the same expense twice. Price and costs are assumed constant throughout the period. All defaults and examples are hypothetical.
Why is contribution margin not the same as gross margin?
Contribution margin per unit = selling price − variable cost per unit. It is what each additional unit contributes toward fixed operating costs and then operating profit. Contribution margin rate = contribution per unit ÷ selling price × 100, and it is undefined when the price is zero.
Gross margin uses revenue minus cost of goods sold, which can include fixed production costs and leave out some variable selling costs. The two are not interchangeable, and neither is automatically net profit. If you are pricing an item from its direct cost, the markup and gross margin calculator covers that separate question.
What are the break-even and target-profit formulas?
- Let F = fixed costs per period, P = selling price, V = variable cost per unit, C = P − V and T = target operating profit.
- When C is positive, theoretical break-even units = F ÷ C.
- Whole units to avoid a loss = ceiling(F ÷ C).
- Whole units for target profit = ceiling((F + T) ÷ C).
- Revenue at Q units = Q × P.
- Operating profit at Q units = Q × C − F.
How the calculator handles inputs and rounding
The results table shows the theoretical threshold as an exact fraction. The numeric card shows a six-decimal approximation, which is not the basis for rounding up.
The module uses exact scaled integers to find the ceiling, so a threshold of exactly 3 units is not accidentally rounded to 4 by floating-point error. Fixed costs and target profit accept cents; unit price and variable cost accept four decimals and keep that precision. Money displays round to cents, with half ties away from zero.
Supported fixed costs and target profit are each up to $1 billion, unit amounts up to $1 million and expected sales up to 10 million whole units. Positive thresholds above 10,000,000 whole units are flagged as outside the supported range, which is not the same as mathematically impossible. The module does not store or transmit inputs.
What does a hypothetical $30 product need to sell?
Inputs. Assume hypothetical monthly fixed costs of $1,000, a $30 selling price and an $18 variable cost per unit.
Formula and result. Contribution is $30 − $18 = $12 per unit, a 40% rate. Theoretical break-even is $1,000 ÷ $12 = 250/3, about 83.333333 units, so the whole-unit requirement is 84 units.
At 83 units, revenue is $2,490 and operating profit is −$4. At 84 units, revenue is $2,520, variable costs are $1,512 and fixed costs are $1,000, leaving $8 operating profit. The whole-unit threshold avoids a loss but does not produce exactly zero profit.
For a $500 target, ($1,000 + $500) ÷ $12 = 125 units, giving exactly $500 operating profit. An expectation of 100 units produces $200.
What to check. This arithmetic does not predict that customers will buy 100 or 125 units. Compare the required volume with sales you can realistically support.
| Scenario | Price / variable cost | Contribution / rate | Whole units to avoid loss | Profit at that volume |
|---|---|---|---|---|
| Base case | $30 / $18 | $12 / 40% | 84 | $8 |
| Lower price | $28 / $18 | $10 / 35.7143% | 100 | $0 |
| Higher variable cost | $30 / $20 | $10 / 33.3333% | 100 | $0 |
| No contribution | $18 / $18 | $0 / 0% | Not achievable | −$1,000 at every volume |
A lower price might change demand, but that response is outside this comparison; only the cost-volume arithmetic changes.
What happens when the threshold is a fraction?
With hypothetical fixed costs of $250, an $8.50 price and a $3.75 variable cost, contribution is $4.75 per unit, about 55.8824% of price. The theoretical threshold is 1000/19, about 52.631579 units.
Round up to 53 units: revenue is $450.50 and operating profit is $1.75. At 52 units, operating profit would be −$3.
A $100 target needs ceiling($350 ÷ $4.75) = 74 units, which yield $101.50 operating profit, while 73 units yield only $96.75. Expected sales of 80 units would yield $130 operating profit.
When does this break-even calculator not fit?
- Your contribution is zero or negative. With zero contribution and positive fixed costs, break-even is not achievable at any volume. With negative contribution, every extra sale increases the loss, and only 0 units avoids a loss when fixed costs are zero.
- You sell several products. A sales mix needs a weighted calculation; this tool models one product. The SBA suggests calculating each product individually when sales vary.
- You need cash flow or after-tax results. Taxes, financing, inventory timing, capacity limits and changing prices are excluded; the output is operating profit under your cost model.
- You are comparing a household purchase. For a subscription billed annually or monthly, use annual versus monthly subscription break-even. For shopping savings against a membership fee, see the warehouse membership break-even guide.
With positive contribution and zero fixed costs, break-even begins at 0 units. With zero contribution and zero fixed costs, every unit count breaks even, but no positive profit target is achievable. The calculator shows text for these cases rather than an infinity number.
How should you use the result?
The SBA’s detailed break-even guide discusses fixed and semi-variable costs and says the break-even point is an estimate, not a complete accounting or financing calculation. These two SBA pages overlap and are not two independent validations.
Treat the whole-unit threshold as a floor for pricing and cost decisions. Expected units are your own assumption, not a prediction from this tool.
Quick decision checklist
- Put fixed costs, price and variable cost on the same period, such as one month.
- Include every per-unit variable cost, including packaging, payment fees and commissions.
- Check that contribution per unit is positive before reading any threshold.
- Compare the whole-unit break-even volume with sales you can realistically make.
- Rerun the numbers whenever price, supplier costs or rent change.
Sources and review
- SBA, Plan your business: single-product break-even formula in units and contribution margin ratio.
- SBA, Break-even point: fixed and semi-variable costs, multiple products and the estimate caveat.
Sources checked September 28, 2026. No SBA calculator output was used to validate these examples; the worked examples, exact-fraction handling, integer ceilings and edge-case rules were checked with local arithmetic tests and the calculator itself.
Prepared with AI-assisted research, drafting, and calculation checks. Not independently reviewed by a human financial professional.
