Free Margin and Break-Even Calculators
Two numbers decide whether a small business survives: how much you keep from each sale, and how many sales you need to cover your fixed bills. These calculators work them out in your browser.
Below the tools, we walk through the formulas with one simple example so you can check the math yourself.

Antique cash register: Thomas Quine, CC BY 2.0
Margin and markup calculator
Enter what an item costs you and what you sell it for.
Break-even calculator
Enter your monthly fixed costs, your price per unit and your variable cost per unit.
Margin vs markup: same profit, two percentages
Margin and markup both start from the same dollar profit: selling price minus cost. The difference is what you divide by. Margin divides the profit by the selling price. Markup divides the profit by the cost.
Margin = (Price minus Cost) divided by Price. Markup = (Price minus Cost) divided by Cost. Because the price is always bigger than the cost when you make a profit, the margin percentage is always smaller than the markup percentage for the same sale.
Mixing them up is a classic pricing mistake. If you want a 50 percent margin and you add a 50 percent markup instead, you end up with only about a 33 percent margin. To hit a target margin, use Price = Cost divided by (1 minus target margin).
Break-even: how many sales cover the bills
Fixed costs stay roughly the same whether you sell one unit or a thousand: rent, software, insurance. Variable costs rise with every unit: materials, packaging, payment fees. The gap between price and variable cost is the contribution margin, the part of each sale that pays down fixed costs.
Break-even units = Fixed costs divided by (Price minus Variable cost per unit). Break-even revenue = Break-even units times Price. Every sale beyond that point adds profit, at least on paper. Remember that profit and cash in the bank are not the same thing.
Worked example: a $20 candle
Say each candle costs you $12 to make and ship, you sell it for $20, and your fixed costs are $3,000 a month.
| Step | Formula | Result |
|---|---|---|
| Profit per candle | $20 minus $12 | $8 |
| Margin | $8 divided by $20 | 40% |
| Markup | $8 divided by $12 | about 66.7% |
| Break-even units | $3,000 divided by $8 | 375 candles a month |
| Break-even revenue | 375 times $20 | $7,500 a month |
| Check with margin | $3,000 divided by 0.40 | $7,500 a month |
| Price for a 50% margin | $12 divided by (1 minus 0.50) | $24 |
Educational tool, not financial advice. Calculators give simple estimates and ignore taxes, discounts, returns and changing costs. Check important decisions with a qualified accountant.
Facts on this page were checked against these sources (updated Oct 1, 2026). Spot an error? Email hello@fireempireshop.com.




