Use the edition you intend to price
For print, match the trim, paper, and interior to the book and use the final formatted page count when available. Odd counts round up to an even effective count before the printing-cost and page-range checks. Unsupported combinations or effective counts outside the selected range prevent a result.
For an eBook, use the file-size assumption relevant to the delivery-cost estimate and choose the royalty option you want to examine. A selected 70% option outside this model's eligible price band falls back to 35% with a warning. It does not mean the calculator verified every other condition for 70% eligibility.
Leave the monthly target blank if you only need per-sale economics. A zero target needs zero copies; a positive target cannot produce a meaningful copy count when the modeled royalty is zero or negative. Compare the valid price rows to understand a boundary, not as a list of recommended prices.
Print and eBook royalties use different deductions
For print, the model applies the royalty rate to list price, then subtracts printing cost. On Amazon.com, the checked print rates are 50% through $9.98 and 60% from $9.99. Printing cost depends on the format, trim class, paper, ink, and effective page count; some short-book branches use a fixed cost. See KDP's paperback costs, paperback royalties, hardcover costs, and hardcover royalties.
For an eligible 70% eBook scenario, delivery cost is subtracted before applying the rate. The 35% branch has no delivery deduction. The local US model rounds file size up to kilobytes and applies the checked $0.15-per-MB delivery rate with a $0.01 minimum. It rounds monetary calculations at defined cent boundaries and displays USD estimates to two decimal places. These are modeled amounts, not a live order quote. KDP's digital pricing rules describe the delivery deduction.
The checked Amazon.com 70% price band is $2.99 through $12.99. Outside that band, this model uses 35%. Its 35% minimum price depends on file size, so a larger file can change price eligibility even though that branch has no delivery deduction. Consult KDP's eBook price requirements for the bands and other conditions. The calculator does not verify account requirements, public-domain status, or the required relationship to a physical edition's price.
A price floor is not a pricing recommendation
The print floor is the minimum modeled price covering printing cost under the applicable rate band. It does not account for editing, design, marketing, or your time. Royalty is therefore not author profit, and the floor says nothing about demand.
Break-even ad spend is a ceiling based on positive royalty per sale. Spending that full amount would consume the modeled royalty before other expenses. Break-even ACoS expresses that ceiling as a share of list price; neither figure recommends a campaign budget or predicts conversion.
Monthly copies divide the target by the modeled cent-based royalty and round up to a whole sale. That is unit arithmetic, not a sales forecast. With no positive royalty, there is no positive ad headroom or meaningful positive-target copy count.
Confirm the scenario in KDP
This calculator covers Amazon.com in USD and standard print distribution, not Expanded Distribution or other marketplaces. It does not model taxes, refunds, promotions, price matching, or account-specific adjustments.
Scenario calculations run locally in your browser. The tool does not contact your Amazon account or submit a price. Check the dated source rules against KDP's current guidance and confirm the actual edition in your publishing workflow before relying on the estimate.