Markup calculator
Markup answers the pricing question directly: I paid this much — what do I charge? Enter a cost and a markup percentage.
Reading the result
The selling price is your cost increased by the markup percentage. The interesting line is the last one: the margin that markup produces. A 100% markup is a 50% margin. A 50% markup is a 33% margin. A 200% markup is a 67% margin. The two numbers converge only at zero, and confusing them is the most common pricing error in small selling.
Common shorthand rules translate like this: keystone pricing (double your cost) is 100% markup; triple is 200% markup, or a 67% margin. Whether a rule like that is enough depends on what else comes out of the sale afterwards — platform fees, shipping supplies, returns, and the time an item waits to sell all eat from the margin, not from your cost.
Questions
Is markup calculated on cost or on price?
On cost, always. If a number is calculated on the selling price it is a margin, not a markup, even if someone calls it a markup.
What markup covers marketplace fees?
Fees are charged on your selling price, so they reduce margin rather than adding to cost. As a rough rule, to protect your intended margin add the platform's fee percentage on top of the markup you would otherwise use, or use the break-even calculator on this site which does that arithmetic properly.
Why does doubling my money only give 50% margin?
Because margin is measured against the sale price, and at double your cost, profit is exactly half the sale price. The percentages use different bases, so the same deal produces two different-looking numbers.