About the Margin Calculator
Margin and markup are easy to mix up, and the difference matters when you price author copies for events, bundles you sell from your own website or merchandise that sits alongside your books. Margin tells you how much of each sale you keep. Markup tells you how much you added on top of your cost. The same price gives two very different percentages.
Choose From cost & price to see margin, markup and profit for a price you already have in mind. Choose Price for target margin when you know the margin you want, for example 60% on books sold at a convention, and need the price that delivers it.
For KDP sales through Amazon, your cost is not the whole story: Amazon keeps a share of each sale before you are paid. Use the KDP Profit Calculator or the KDP Royalty Calculator for Amazon sales, and this tool for anything you sell directly. The guide on how to price a KDP book covers the wider pricing decision.
How It Works
Profit is the selling price minus the cost per unit.
Margin divides that profit by the selling price. Markup divides it by the cost. If the cost is zero, markup cannot be calculated and is shown as a dash.
In target-margin mode the calculator rearranges the margin formula to find the price: cost divided by one minus the margin. Margins must be below 100%, because a 100% margin would require an infinite price.
Formula
- Profit
- Profit = Price − Cost
- Margin
- Margin = Profit ÷ Price × 100
- Markup
- Markup = Profit ÷ Cost × 100
- Price for target margin
- Price = Cost ÷ (1 − Margin ÷ 100)
Example
Selling author copies at a book fair
- Cost per copy: $4.85 (author copy printing plus your share of shipping).
- Selling price: $15.00.
- Profit: $15.00 − $4.85 = $10.15.
- Margin: $10.15 ÷ $15.00 = 67.67%.
- Markup: $10.15 ÷ $4.85 = 209.28%.
Each copy earns $10.15, a 67.67% margin or a 209.28% markup.
Important Notes
- Results cover one unit. Multiply the profit by your expected sales for a total.
- Include every per-copy cost you pay, such as printing, shipping, packaging and card fees, for a realistic margin.
- Fixed costs like a table fee or a cover design are not included. Use the KDP Break-Even Calculator to see how many sales cover them.
- Prices are rounded to the nearest cent in target-margin mode.
- A price below cost produces a negative margin, which is flagged.
Frequently Asked Questions
What is the difference between margin and markup?
Margin is profit as a share of the selling price. Markup is profit as a share of the cost. A book that costs $5 and sells for $10 has a 50% margin but a 100% markup.
Which one should I use to price author copies?
Margin is usually more useful, because it tells you what share of every sale you keep after costs. Markup is handy when a supplier or retailer quotes terms as "cost plus" a percentage.
Why can't I enter a 100% margin?
A 100% margin would mean zero cost or an infinite price. The calculator accepts margins up to 99.99%.
Can I use this for KDP paperback sales on Amazon?
Only loosely. On Amazon, your royalty already deducts printing cost and Amazon's share. The [KDP Royalty Calculator](/tools/kdp-royalty-calculator) models that precisely. This tool is best for direct sales.
Does it work in other currencies?
Yes. Choose your currency and the results are formatted to match. The maths is the same in every currency.
Related KDP Tools
- KDP Profit CalculatorTurn royalties, ad spend and other costs into net profit, profit per book and margin.
- Percentage CalculatorPercent of a number, percentage change and what-percent-of calculations.
- Discount CalculatorSee the sale price, savings and royalty impact of a price promotion.
- Book Deadline CalculatorWork out daily word targets or your finish date from your writing pace.
- Word CounterA fast, private word counter with top-word frequency.
- Character CounterCount characters with and without spaces, plus bytes and limits.