What is a break-even calculator?
A break-even calculator tells you the exact point at which your business stops losing money and starts making it. You give it three numbers — your monthly fixed costs, the price you sell each unit for, and the variable cost of producing and delivering one unit — and it returns your break-even point in both units and revenue. The optional target-profit field goes one step further and shows how many units you'd need to sell to clear a specific profit number, not just cover costs.
It's the single most useful piece of math a new founder can run before launch. Pricing on a hunch is how good products quietly go broke; a break-even number turns “I think this works” into “I need to sell 112 units a month, which is about four a day.” That's a target you can actually plan around.
The break-even formula, explained
The formula has two moving parts. The first is contribution margin — the dollars each sale puts toward your fixed costs:
Contribution margin = Selling price − Variable cost per unit
The second part divides your fixed costs by that margin to find how many sales it takes to cover them:
Break-even units = Fixed costs ÷ Contribution margin
Multiply break-even units by your price and you get break-even revenue — the dollar figure you need to hit each month. The same logic extends to a profit target: add your desired profit to fixed costs before dividing, and you get the units required to earn that profit on top of covering everything.
One rule the calculator enforces: your contribution margin must be positive. If your variable cost per unit is equal to or higher than your price, every sale loses money, and no volume of sales will ever break even. The fix is always to raise the price or cut the per-unit cost — selling more cannot rescue a negative margin.
A worked example
Say you run a small candle brand. Your fixed costs — workshop rent, your design software, and a base ad budget — total $2,000 a month. You sell each candle for $30, and each one costs you $12 once you add wax, the jar, packaging, shipping, and your payment processor's fee.
- Contribution margin = $30 − $12 = $18 per candle (a 60.0% margin).
- Break-even units = $2,000 ÷ $18 = 112 candles a month (rounded up).
- Break-even revenue = 112 × $30 = $3,360 a month.
- To clear a $1,000 monthly profit: ($2,000 + $1,000) ÷ $18 = 167 candles a month.
That's the whole point of the exercise. “112 candles a month” is roughly four sales a day — a concrete, testable target. If four a day feels out of reach, you now know to adjust the plan before you've spent the rent, not after.
Benchmarks: is your margin healthy?
Your break-even point is only as good as the contribution margin behind it, so it's worth knowing where yours sits against the market. A few current reference points:
- The average e-commerce store runs around a 60–65% gross margin, with 60–70% considered the healthy range for sustainable, profitable scaling, according to a 2025–2026 analysis of thousands of stores by TrueProfit.
- Margins swing hard by category: Onramp Funds reports beauty brands at 50–70% gross margin while electronics sit at just 15–25% — which is why a candle business breaks even far faster than a gadget store.
- On the bottom line, the best e-commerce businesses reach 20%+ net margins while the average is closer to 10%, per Onramp Funds. Damodaran's widely cited NYU Stern industry margin dataset shows online retail operating margins compressed into the low single digits once fulfillment and ad spend are counted.
- As a planning rule of thumb, industry guidance suggests keeping total operating expenses under 30% of revenue to stay comfortably profitable (Onramp Funds).
If your contribution margin is well below your category's typical gross margin, that's a signal your pricing or per-unit costs need attention before you scale spending.
How to improve your break-even point
A lower break-even point means you reach profitability on fewer sales — which de-risks the whole business. Three levers move it:
- Raise your price. Because break-even divides fixed costs by contribution margin, even a small price increase widens the margin and drops the units you need. Going from $30 to $33 on the candle example cuts break-even from 112 to about 96 units.
- Cut variable cost per unit. Negotiate supplier pricing, batch-buy packaging, lower shipping spend, or reduce payment-processing fees. Every dollar you trim from variable cost flows straight into contribution margin.
- Trim fixed costs. Cancel unused software, renegotiate recurring bills, and resist adding fixed overhead before revenue justifies it. Lower fixed costs lower the bar you have to clear.
Re-run the calculator after each change. Watching the break-even number move in real time is the fastest way to see which lever matters most for your business.
Break-even calculator FAQ
What is a break-even calculator?
A break-even calculator tells you exactly how many units you need to sell — and how much revenue you need to earn — before you stop losing money and start making a profit. You enter your monthly fixed costs, your selling price per unit, and your variable cost per unit, and it returns your break-even point in units and dollars instantly. It's the fastest way to know whether your pricing actually works before you commit to it.
What is the break-even formula?
Break-even units = fixed costs ÷ (price per unit − variable cost per unit). The denominator — price minus variable cost — is your contribution margin: the dollars each sale contributes toward covering fixed costs. Once contribution margin × units sold equals your fixed costs, you've broken even. Multiply break-even units by your price to get break-even revenue.
What is contribution margin and why does it matter?
Contribution margin is your selling price minus the variable cost of producing and delivering one unit (product cost, shipping, packaging, payment fees). It's the money left over from each sale to put toward fixed costs and, eventually, profit. A higher contribution margin means you break even on fewer sales. If your contribution margin is zero or negative, you can never break even at any volume — you'd lose money on every order.
What counts as a fixed cost versus a variable cost?
Fixed costs stay roughly the same no matter how much you sell: rent, software subscriptions, salaries, insurance, and your base marketing budget. Variable costs scale with each unit sold: the product itself, shipping, packaging, transaction fees, and per-order fulfillment. Putting a cost in the wrong bucket is the most common reason a break-even estimate is off, so sort carefully.
How do I lower my break-even point?
Three levers move it. Raise your price (even a small increase widens contribution margin and drops the units you need). Cut variable cost per unit by negotiating supplier rates, reducing shipping spend, or lowering payment fees. Or trim fixed costs by cancelling unused software and renegotiating recurring bills. Because break-even units divide fixed costs by contribution margin, improving the margin usually moves the number fastest.
Is this break-even calculator free?
Yes — completely free, instant, and no signup required. Enter your numbers and the result updates live. You can also email yourself a clean PDF of the results. The calculator runs entirely in your browser, so your figures stay private.
Keep going
Once you know your break-even point, sketch the full picture with our e-commerce business plan generator and pressure-test demand with the niche finder. Want the definitions behind the math? See contribution margin and break-even point in the glossary.