Business Calculators

About these calculators

Three calculators support pricing and small-business planning. Profit Margin Calculator takes a cost and a selling price and returns the profit, the margin (profit as a share of the selling price) and the markup (profit as a share of cost), which are easy to confuse. It shows markup as unavailable when the cost is zero, and it accepts selling below cost, giving negative results. ROI Calculator takes an initial investment and a final value and shows the net gain or loss and the return on investment as a percentage. If you also enter a holding period in years, it adds an annualized return.

Break-Even Point Calculator takes fixed costs, the selling price per unit and the variable cost per unit. It shows the contribution margin per unit, the number of units needed to cover the fixed costs, rounded up to a whole unit, and the revenue at that point. It reports an error if the price is not higher than the variable cost, because you could never break even. These are straightforward formulas. They leave out taxes, fees, overhead you have not included in the inputs, and changes in price or cost over time. Each page shows its formula and a worked example, and the calculations run in your browser.

Here is each tool with real numbers. Something that costs 80 and sells for 100 has a profit of 20, a margin of 20.00% and a markup of 25.00%: the same 20 is divided by the selling price for the margin and by the cost for the markup. An investment of 5,000 that grows to 6,500 over 3 years shows a net gain of 1,500, an ROI of 30.00% and an annualized return of 9.14%, while 5,000 falling to 4,000 shows a loss of 1,000 and an ROI of -20.00%. With fixed costs of 12,000, a price of 25 and a variable cost of 10, the contribution margin is 15, break-even is 800 units and break-even revenue is 20,000.00. If you set the price equal to the variable cost, the tool refuses, because no number of sales could recover the fixed costs.