Use this profit calculator to estimate the profit from a sale or batch of sales using your purchase price, selling price, units sold, commission rate, and sales tax or VAT rate. It returns revenue, profit in dollars, and profit as a percentage of revenue.
Important: the calculator treats both prices as tax-inclusive at the same rate and applies commission to the difference between selling price and purchase price—not to the full selling price. Check that these assumptions match your transaction before relying on the result.
How to use the profit calculator
- Purchase price: enter the cost of one item, including sales tax or VAT. Use a per-unit amount, not the total cost of the batch.
- Selling Price: enter the tax-inclusive price you charge for one item. If you need to convert between tax-exclusive and tax-inclusive prices, use the sales tax calculator.
- Units sold: enter the number of items sold or the quantity you want to evaluate. The calculation assumes every unit has the same purchase and selling prices.
- Commission Fee: enter the percentage applied to the tax-inclusive price difference. Enter 0 if no commission applies. A fee charged on the full sale price will not be modeled correctly by this field.
- Sales Tax (VAT): enter the percentage used to remove tax from both prices. Enter 0 if no tax adjustment is needed.
Enter percentage rates as whole numbers: use 5 for 5%, not 0.05. Keep purchase and selling prices in the same currency; the calculator labels monetary values in dollars.
Profit formula used by this calculator
The basic profit formula is revenue minus costs. This calculator uses a specific version that adjusts the purchase-to-sale price difference for tax, then deducts a commission calculated on that difference before tax is removed.
Using p for selling price, k for purchase price, z for units sold, v for the tax percentage, and f for the commission percentage:
Revenue = [p ÷ (1 + v/100)] × z
Profit = [(p − k) ÷ (1 + v/100)] × z − [(p − k) × z × f/100]
Profit percentage = (Profit ÷ Revenue) × 100
Dividing by 1 + v/100 removes tax already included in a price. For example, a $120 price including 20% VAT becomes $100 before VAT—not $96.
When both tax and commission are zero, the profit calculation simplifies to (selling price − purchase price) × units sold.
Worked example: profit from 50 units
Suppose you buy an item for $72 and sell it for $120, both including 20% VAT. You sell 50 units and enter a 5% commission.
| Calculation | Working | Result |
|---|---|---|
| Revenue excluding tax | ($120 ÷ 1.20) × 50 | $5,000 |
| Price difference excluding tax | [($120 − $72) ÷ 1.20] × 50 | $2,000 |
| Commission deduction | ($120 − $72) × 50 × 0.05 | $120 |
| Profit | $2,000 − $120 | $1,880 |
| Profit percentage | ($1,880 ÷ $5,000) × 100 | 37.6% |
The modeled profit per sale is $37.60: $1,880 divided by 50 units. To use the tool as a profit per sale calculator directly, enter 1 for Units sold.
What your profit result means
The dollar profit is the amount remaining under the calculator’s purchase-cost, tax, and commission assumptions. The percentage shows that amount relative to tax-exclusive revenue. In the example, 37.6% means $0.376 remains from each $1 of revenue before costs not included in the model.
This is not net business profit. The calculator does not separately deduct shipping, packaging, advertising, labor, returns, income tax, or fixed costs such as rent. A positive result therefore does not guarantee that your business is profitable overall.
The percentage is a revenue-based margin, not markup on purchase cost. Increasing units sold multiplies revenue and dollar profit proportionally, but leaves the percentage unchanged when all other inputs stay the same.
When the result needs extra care
- Fees based on sales revenue: many payment processors and marketplaces charge a percentage of the selling price, sometimes plus a fixed fee. That is different from this calculator’s commission formula. In the example, 5% of the full tax-inclusive sales total would be $300, rather than the $120 deducted here.
- Different tax treatment: one tax rate is applied to both prices. Different purchase and sales rates, nonrecoverable purchase tax, or other tax rules may require a separate calculation. This tool is not a tax-liability calculator.
- Selling below purchase price: when the price difference is negative, the commission term also becomes negative, reducing the modeled loss. Actual transaction fees generally remain payable, so use a separate cost calculation for loss-making sales.
- Zero revenue: if selling price or units sold is zero, profit as a percentage of revenue is mathematically undefined.
Use the results to make pricing decisions
Compare your current price with a proposed discount while keeping purchase cost and quantity unchanged. The difference in dollar profit shows how much the discount costs across the batch. Then test a lower supplier price to see whether purchasing savings could offset that reduction.
For a more complete decision, divide any additional batch costs by units sold and compare that per-unit amount with your modeled profit per sale. In the example, $10 of additional costs per item would reduce the $37.60 modeled profit to $27.60 before remaining overhead and taxes.
Related calculators for your next step
- Profit Goal Calculator: work toward a target profit when planning sales.
- Margin Calculator: examine the relationship between cost, selling price, and margin.
- Break-Even Point Calculator: assess the sales needed to cover fixed and variable costs.
- Margin of Safety Calculator: measure how far sales can fall before reaching break-even.
For other business models and broader performance measures, use the MRR calculator to track monthly recurring revenue, or explore Economic Value Added to evaluate earnings after a charge for capital. These answer different questions from profit on an individual sale.
Build a calculator around your pricing model
If your business uses different fee bases or additional costs, Calcopolis lets you build a customized profit or ROI calculator. Give website visitors estimates based on your pricing assumptions before they request a quote.