Product Pricing Calculator (Cost-Plus / Target Margin)
Enter your fully-loaded unit cost — materials, labor time, overhead allocation, and platform fees — and the target gross margin you want to earn. The calculator solves the selling price for you using the correct margin formula, then shows how that price compares to traditional wholesale (2×) and retail (4×) keystone rules of thumb.
Unit cost components
Pricing target
Selling price (target 40% margin)
$50.00
price = unitCost / (1 − margin − fees) = $30.00 / 0.60
Gross profit / unit
$20.00
Price comparison
| Strategy | Price | Margin | Profit |
|---|---|---|---|
| Target margin | $50.00 | 40.00% | $20.00 |
| Wholesale keystone (2×) | $60.00 | 50.00% | $30.00 |
| Retail keystone (4×) | $120.00 | 75.00% | $90.00 |
Price by margin target
How it works
Your fully-loaded unit cost is every dollar you spend to produce one unit: raw materials or COGS, labor (hours × hourly rate), and any fixed overhead you allocate per unit such as rent, equipment depreciation, or packaging. Platform fees — Etsy's 6.5% transaction fee, Amazon's 15% referral fee, Shopify Payments' processing cut — come off the selling price, not the cost, so they must be factored into the price formula separately. The calculator builds all four components into a single unit cost and then solves the price that achieves your chosen margin after fees are deducted.
The formula is price = unitCost / (1 − targetMargin − fees%). This is the margin-on-price formula, not a markup formula. The difference matters enormously: adding 40% to cost gives a 40% markup — but only a 28.6% margin, because margin divides gross profit by the selling price, not by cost. If you use cost × (1 + margin%) you will consistently underprice. The correct formula works the other way: to keep 40 cents of every dollar in revenue as profit, you divide cost by the 60 cents left after profit is removed — price = cost / (1 − 0.40).
The comparison table shows two traditional keystone benchmarks alongside your target-margin price. Wholesale keystone prices a product at 2× unit cost (a 50% gross margin before fees); retail keystone at 4× (75% gross margin before fees). These rules of thumb date from brick-and-mortar retail where fees were minimal. In ecommerce, platform fees directly reduce those margins — a 15% referral fee turns a 50% keystone margin into 35%. The table makes that erosion visible row by row, so you can decide whether the keystone rule or a fee-adjusted target margin makes more sense for your channel.
Frequently asked questions
What is the difference between margin and markup, and why does it matter for pricing?+
Margin is gross profit divided by selling price; markup is gross profit divided by cost. They use the same profit number but different denominators, so the same percentage means a very different price. A 40% markup on a $30 cost sets the price at $42, yielding a margin of only 28.6% ($12 profit ÷ $42 price). A 40% margin on a $30 cost sets the price at $50 ($30 ÷ 0.60), yielding exactly the 40% margin you intended. If your buying decisions, break-even analysis, or investor conversations use margin as the metric — and most do — you must price using the margin formula, not markup. Using the wrong formula and your actual margins will always be lower than you planned.
Should platform fees go into the unit cost or the pricing formula?+
Platform fees belong in the pricing formula, not the unit cost, because they are charged as a percentage of the selling price — a number you have not set yet when you are calculating cost. If you add an estimated fee dollar amount to unit cost and then price using cost/(1−margin), you create a circular dependency (the fee estimate was based on a price that changes when you add to cost). The correct approach is to treat fees as a percentage that reduces your net revenue: price = unitCost / (1 − margin − fees%). This calculator does exactly that. The result is a price that hits your target margin after fees are deducted, with no circularity and no manual iteration.
What is keystone pricing and is it still useful?+
Keystone pricing is the rule of thumb of pricing a product at 2× cost (wholesale) or 4× cost (retail). It was designed for physical retail with predictable, low fee structures, where 50% gross margin left enough room for operating costs and profit. For ecommerce sellers it is a useful starting point but rarely the right answer: platform fees (6–20%), shipping, returns, and ad costs can erode a 50% keystone margin below your actual break-even point. This calculator shows keystone prices and their fee-adjusted margins side by side with your target-margin price, so you can see at a glance whether the keystone rule is conservative or dangerously optimistic for your specific channel.