Formula
Profit = SP − CP Loss = CP − SPProfit % = Profit ÷ CP × 100 Loss % = Loss ÷ CP × 100SP = CP × (1 ± %/100) CP = SP ÷ (1 ± %/100)
- CP — cost price
- SP — selling price
Profit and loss percentages are measured against the cost price.
Worked examples
Bought at 100, sold at 120
- What do you know?
- Cost price and selling price
- Cost price
- 100
- Selling price
- 120
Profit
20.00
Profit % (on cost price): 20%
Margin (on selling price): 16.6667%
12% profit on a cost of 500
- What do you know?
- Cost price and a profit/loss % → find selling price
- Cost price
- 500
- Profit or loss?
- Profit
- Percentage
- 12 %
Selling price
560.00
Profit amount: 60.00
How it works
Buy for 100 and sell for 120 and the profit is 20, which is 20 ÷ 100 × 100 = 20% of the cost price. The tool also shows the margin — profit as a share of the selling price (20 ÷ 120 = 16.67%) — because retailers often quote that instead. Markup (on cost) and margin (on selling price) are different numbers for the same trade.
To set a price, multiply the cost by one plus the profit percentage: a 12% profit on 500 means selling at 500 × 1.12 = 560. To find what was paid, divide the selling price by the same factor. If the selling price includes a discount see Discount Calculator; for tax-inclusive prices see GST Calculator.
Assumptions and limits
- Profit and loss percentages use the cost price as the base, the usual textbook rule.
- Amounts are rounded to two decimal places.