Break-Even Point Calculator
Calculate the number of units you must sell at a given price to cover all of your costs — the moment a business starts generating profit instead of losing money on each transaction. Enter your total fixed costs (rent, salaries, software, insurance), your variable cost per unit (raw materials, packaging, payment processing), and your selling price per unit, and the calculator returns the break-even quantity. This is one of the most important numbers in starting or pricing any product: it tells you whether the business model is even viable, how much volume you need, and how sensitive profitability is to price and cost changes.
About this calculator
The formula is: break-even units = fixed costs ÷ (selling price per unit − variable cost per unit). The denominator is the contribution margin per unit — the dollars each sale contributes toward covering fixed costs after variable costs are paid. Once you have sold enough units for total contribution to equal total fixed costs, you have broken even; every additional unit sold after that adds its contribution margin directly to profit. Fixed costs are expenses that do not change with the number of units sold in the short term — rent, salaried staff, base utilities, SaaS subscriptions, insurance, depreciation. Variable costs scale linearly with unit volume — raw materials, packaging, shipping, sales commissions, credit-card processing fees. Selling price is the per-unit revenue you actually receive (gross, before any discounts or returns). Edge case: if selling price equals or is below variable cost per unit, the contribution margin is zero or negative, meaning every sale either contributes nothing or actively loses money — the business cannot break even at any volume, and the calculator flags this with an error rather than returning infinity or a negative number. The break-even formula assumes a single product, constant prices, constant unit costs, and that fixed costs do not step up at higher volumes (i.e., you do not need to hire a second factory or another warehouse partway through). In real businesses, costs often have step functions and prices change with volume — the formula is a useful planning tool, not a precise prediction.
How to use
Example 1 — A small handmade-goods business. You rent a workshop for $2,000/month, pay yourself a base salary of $3,000/month, spend $500 on insurance and software subscriptions, for total fixed costs of $5,500/month. Each candle costs $4 in wax, wicks, jars, packaging, and shipping (variable cost), and you sell each one for $25. Enter 5500 for Fixed Costs, 4 for Variable Cost per Unit, and 25 for Selling Price per Unit. Result: 262 candles. Verify: contribution margin per candle = 25 − 4 = $21, and 5500 ÷ 21 ≈ 261.9, rounded to 262 units. ✓ You need to sell 262 candles a month just to cover costs; the 263rd candle is where profit begins. At that volume your revenue is 262 × $25 = $6,550 and total costs are $5,500 + (262 × $4) = $6,548 — break-even confirmed. Example 2 — A SaaS startup. Monthly fixed costs are $80,000 (engineering salaries, office, AWS reserved capacity, marketing baseline). Variable cost per customer is $8/month (per-seat AWS usage, payment processing, support tickets). Subscription price is $49/month. Enter 80000, 8, and 49. Result: 1,952 customers. Verify: contribution margin = 49 − 8 = $41, and 80000 ÷ 41 ≈ 1951.2, rounded up to 1,952. ✓ Once the company hits about 2,000 paying customers it covers its baseline burn; each additional customer adds $41 toward profit (before considering acquisition cost). This number tells the founders exactly what milestone separates "burning cash" from "self-sustaining" and lets them plan runway and fundraising around a concrete target.
Frequently asked questions
What is contribution margin and how does it relate to break-even?
Contribution margin is selling price minus variable cost — the dollars each unit sold "contributes" toward covering fixed costs and (after break-even) toward profit. Expressed as a ratio, contribution margin per unit ÷ selling price = contribution margin ratio, telling you the percentage of each sale that flows to fixed-cost coverage and profit. A product with a high contribution margin ratio (software, digital downloads) breaks even at relatively low volumes because each sale carries a lot of the load; a product with a low contribution margin ratio (groceries, commodity manufacturing) requires huge volumes to break even and is extremely sensitive to price changes. Break-even in units uses the per-unit contribution margin, while break-even in revenue (a useful related metric) is fixed costs ÷ contribution margin ratio. Understanding contribution margin is the foundation of pricing, cost-cutting, and product-mix decisions in any business.
What is the margin of safety and why does it matter?
Margin of safety is the gap between your actual sales (or forecast sales) and the break-even point, expressed in units, dollars, or as a percentage. If you break even at 262 units and actually sell 400, your margin of safety is 138 units, or 35% — meaning sales would have to drop by 35% before you started losing money. A large margin of safety means the business can absorb downturns; a thin margin (5–10%) means a small dip in demand or a small increase in costs can wipe out profitability. For new businesses, lenders and investors look at break-even projections to judge how realistic the plan is — a model that requires 95% of theoretical capacity utilisation to break even is a very different proposition from one that breaks even at 30% utilisation. Margin of safety is what turns break-even from a single point into a meaningful risk metric.
How does break-even analysis change with multiple products?
When you sell multiple products, you cannot just sum unit break-evens because each product has a different contribution margin per unit. The standard approach is a weighted-average contribution margin: weight each product's contribution margin by its share of expected revenue mix, then divide total fixed costs by the weighted-average margin to get break-even revenue. For example, if Product A has a $20 contribution and is 60% of revenue, and Product B has a $5 contribution and is 40%, the weighted-average contribution is (20×0.6 + 5×0.4) = $14; total fixed costs ÷ 14 gives break-even in units of the typical "mix bundle". The shortcut breaks down if the mix changes — selling more of the lower-margin product than expected pushes the real break-even higher. For complex multi-product businesses, a spreadsheet model with the actual expected mix is more accurate than this single-product formula.
What are the most common mistakes people make in break-even analysis?
The biggest is misclassifying costs — putting a variable cost into the fixed bucket (or vice versa) distorts the contribution margin and produces a wildly wrong break-even. Salaries are tricky: a salaried employee is fixed in the short run but becomes variable when you need to hire a second person to handle higher volume. The second is ignoring step-function fixed costs — at some volume you outgrow the warehouse, need a second customer-service agent, or hit AWS reserved-capacity limits, and the "fixed" cost line jumps. The third is forgetting that pricing affects volume: dropping your price to undercut a competitor lowers your contribution margin but might raise unit volume, and the break-even calculation alone cannot tell you whether the net effect is positive. The fourth is using break-even as a target rather than a floor — covering costs is not a business goal, generating returns above cost of capital is. Finally, people often forget that break-even is a snapshot at one price and one cost structure; sensitivity analysis (re-running the calc with ±10% on each input) reveals which variables your business is most exposed to.
When should I not use this calculator?
Skip this calculator for businesses where pricing varies by customer (B2B contracts with negotiated rates), where the product is bundled with services that have their own cost structure, or where unit volume is so low that the "contribution margin per unit" framing is not meaningful (custom consulting, bespoke manufacturing). It is the wrong tool for service businesses with no clear "unit" — for those, use a break-even-in-revenue calculation based on average contribution margin ratio. Do not use it for subscription businesses without modelling churn separately; the relevant question for SaaS is not "how many customers do we need to break even" but "what LTV/CAC ratio supports a sustainable business given churn". It also assumes selling price exceeds variable cost — if it does not, no break-even exists and the calculator returns an error message. Finally, do not use a single break-even number for multi-year planning; rerun the analysis quarterly as costs and prices shift.