Skip to content

Keystone Pricing Calculator

Double the cost — and whether that is enough.

Written and maintained by Mohit PatelLast checked August 4, 2026How we build these
% of price

Keystone price

$30.00

50% margin before other costs

Double keystone$45.00
Fees & advertising$6.00
Margin after those costs30.0%
Price for 50% net margin$50.00

How the Keystone Pricing Calculator works

Keystone means doubling the cost — a 100% markup and a 50% margin. It survives as a default because it is easy and roughly covers a traditional store's overheads. Whether it covers yours is a different question.

Not financial advice. Marketplace fees change, and they vary by country, plan and seller status. Every rate here is an editable default, not a quoted price — check the platform's current fee schedule before you price a product against it. This is not tax or business advice.

Frequently asked questions

What is keystone pricing?

Setting retail at twice the wholesale or unit cost. A £15 cost becomes a £30 price. In margin terms that is 50%, which is where the century-old convention comes from.

Is keystone still relevant?

As a starting point, yes. As a rule, less so — online sellers face marketplace fees and advertising costs a traditional shop did not, which is why many now use double or triple keystone in categories that support it.

What is triple keystone?

Three times cost, giving a 66.7% margin. Common in jewellery, gifts and fashion accessories where the cost base is low relative to perceived value and returns or slow turnover need absorbing.

When does keystone fail?

When per-unit costs beyond the product are high — heavy shipping, high return rates, expensive acquisition. A 50% margin sounds comfortable until 15% goes to fees and another 20% to advertising.

Related calculators