Break-even point calculator
How many units a month cover your fixed costs, and how far above or below that line are you? Enter your numbers; the result updates as you type.
Result
Fill in fixed costs per month, selling price per unit, variable cost per unit to see the result.
How it works
Each unit you sell pays its own variable costs first: the product, packaging, shipping and the payment fee. What is left, the contribution margin, pays the fixed costs. Break-even is the number of units whose contribution margins add up to your fixed costs. Past it, each extra unit's contribution margin is profit.
contribution margin = price - variable cost contribution margin ratio = contribution margin ÷ price break-even units = fixed costs ÷ contribution margin, rounded up to a whole unit break-even sales = fixed costs ÷ contribution margin ratio profit = units × contribution margin - fixed costs margin of safety = (units - break-even units) ÷ units
What each term means
- Fixed costs
- Costs that stay the same within your normal range of volume: salaries, rent, software, insurance, a set ad budget.
- Variable cost per unit
- What one more unit costs you: the product (landed), packaging, the shipping you pay, payment fees, per-order fulfillment fees.
- Contribution margin
- Price minus variable cost: what one unit adds towards fixed costs and profit.
- Contribution margin ratio
- The contribution margin as a share of the price: how much of each unit of sales is left to pay fixed costs.
- Margin of safety
- How far sales can fall before you reach break-even, as a share of your current sales. It is measured against the exact threshold, not the rounded-up units.
What it assumes: the price and the variable cost per unit hold across the volume, and fixed costs stay fixed. Bulk buying prices, volume discounts or a step up in fixed costs, such as a second warehouse, move the line; run the calculator again with the numbers for that volume.
Sources: OpenStax, Managerial Accounting 3.2: break-even point in units and dollars (read 26 September 2026) and OpenStax 3.5: margin of safety (read 26 September 2026).
Worked example
Example numbers, round on purpose, not a real store:
- Fixed costs per month
- €12,000
- Selling price per unit
- €50
- Variable cost per unit
- €30
- Units sold per month now
- 800
- 1Contribution margin: €50 - €30 = €20.00
- 2Contribution margin ratio: €20 ÷ €50 = 40%
- 3Break-even units: €12,000 ÷ €20 = 600 units a month
- 4Break-even sales: €12,000 ÷ 40% = €30,000 a month
- 5Profit at 800 units: 800 × €20 - €12,000 = €4,000 a month
- 6Margin of safety: (800 - 600) ÷ 800 = 25%
So this example store covers its fixed costs at 600 units a month and makes €4,000 at 800. A quarter of its sales could disappear before it made a loss. Want to see what one unit really leaves after shipping, fees and ads? Use the contribution margin calculator.
Frequently asked questions
What is a break-even point?
The sales volume at which revenue equals total costs, so profit is zero. Below it you make a loss; above it, each unit's contribution margin is profit. You can count it in units (fixed costs divided by the contribution margin per unit) or in sales (fixed costs divided by the contribution margin ratio).Which costs are fixed and which are variable?
Fixed costs stay the same when your volume changes within a normal range: salaries, rent, software, insurance. Variable costs rise with every unit: the product, packaging, the shipping you pay, payment fees and per-order fulfillment fees. Ad spend can be either: a set monthly budget is fixed, a cost per order that rises with sales is variable. Count each cost in one place only.Should I count in units or in orders?
Either, as long as the price and the variable cost describe the same thing. If most orders hold several items, count in orders: enter your average order value as the price and the variable cost of an average order. The break-even point then comes out in orders a month.What does the margin of safety tell me?
How far your sales can fall before you reach break-even, as a share of your current sales. A 25% margin of safety means a quarter of your sales could disappear before you make a loss. It is a quick way to see how exposed you are to a slow month.How do I lower my break-even point?
Raise the contribution margin per unit, by raising the price or cutting a variable cost, or cut fixed costs. A price rise only helps if customers keep buying at the new price, so weigh it against the sales it may cost you; the discount calculator shows the same trade-off in the other direction.Why is break-even sales not exactly units times price?
Break-even units are rounded up to a whole unit, because you cannot sell part of one. Break-even sales is the exact threshold, fixed costs divided by the contribution margin ratio, so it can be a little less than the rounded units times the price.
In the glossary: profit margin.
Next: which channels bring your orders?
Break-even is a number of orders. Which channels bring those orders, and how long buyers take to decide, is the next question. Your GA4 export already holds how long your buyers take and which channels they touch. First finding free, in your browser; the full read is €99.