Profit margin and markup without the percentage trap
Start with prices excluding VAT
For a business, collected VAT is normally neither revenue nor profit. Compare cost and selling price before VAT. If you only know the customer price including VAT, remove the tax first with the VAT calculator.
Margin and markup use different bases
Gross profit is selling price minus cost. Margin divides gross profit by selling price; markup divides it by cost. A product costing 600 and selling for 1,000 therefore produces 400 gross profit, a 40% margin, and a 66.7% markup.
Price from a target margin
Use price = cost / (1 − margin). A 40% target on a cost of 600 requires a selling price of 1,000 before VAT. Simply adding 40% to cost would only create a 28.6% margin.
Gross profit is not net profit
Shipping, packaging, commission, waste, returns, card fees, premises, administration, and labour may still consume the result. Include direct costs in the cost price, then check whether the remaining gross profit can cover overhead. Test a minimum sustainable price, your target, and the market price instead of trusting one percentage.