Calculators for self-published books
Spine widths, cover sizes, printing costs and royalties, worked out from the rates KDP publishes. Free, no sign-up, and every tool explains the math.
Paperback
- KDP Spine Width CalculatorSpine width from page count and paper type
- KDP Cover Size CalculatorFull wrap cover dimensions with bleed, in inches, mm and pixels
- KDP Margin and Bleed CalculatorInterior page size, gutter and outside margins
- Planner and Journal Page Count CalculatorInterior pages, spine and print cost for low-content books
Ebook
- Kindle eBook Royalty Calculator35% vs 70% royalty with delivery costs and VAT
- Kindle Price Checker for Every Marketplace70% royalty price bands and royalty in all 9 Kindle currencies
- Kindle Delivery Cost CalculatorDelivery fee per sale and the file size where 35% beats 70%
- Kindle eBook Cover Size CalculatorCheck pixels and the 1.6:1 ratio, crop a paperback front cover
- Kindle Box Set Price CalculatorBox set royalty against selling each book, with the KU page cap
- KENP Pages Read CalculatorKindle Unlimited earnings from pages read
- KDP Select vs Wide CalculatorKindle Unlimited income against selling on other ebook stores
Money
- KDP Printing Cost CalculatorPrint cost per copy for every ink, trim and marketplace
- KDP Paperback Royalty CalculatorRoyalty per copy, minimum price and price for a target royalty
- KDP Hardcover Royalty CalculatorHardcover printing cost, royalty and minimum price
- Book Break-Even CalculatorCopies and months to earn back cover, editing and ad costs
- Break-Even ACoS Calculator for BooksAmazon Ads ACoS, ROAS and the highest bid that still profits
- Book Price Change CalculatorSales you need at a new price to earn the same
- Ebook vs Paperback vs Hardcover Royalty CalculatorWhat one book earns per copy in each KDP format
- Author Income Goal CalculatorCopies a day you need to sell to reach a monthly income
- Co-Author Royalty Split CalculatorRepay shared costs, then split royalties by percentage
- Series Read-Through CalculatorRead-through rate and what each book 1 reader is worth
Writing
- Word Count to Page Count CalculatorHow many pages your manuscript will print to
- Words per Day CalculatorDaily word count to finish your draft by a deadline
Files & ISBN
Guides
- Kindle's 70% Royalty Now Goes Up to $12.99: What to Reprice
- What KDP Charges to Print a Paperback, With Every Table
- Why $9.99 Is the Most Important Paperback Price on KDP
- KDP Groundwood Paper: Cost, Eligibility and the Cover Catch
- KDP Select or Wide? Three Authors Run the Numbers
- How to Price a Kindle Box Set Without Losing Money
Why these tools
Publishing a paperback means getting a handful of numbers exactly right: the spine width for your cover, the gutter for your page count, the printing cost that comes out of every sale, and the list price where the royalty rate changes. Each calculator here uses the formulas and rate tables from KDP's own help pages, shows its working, and links to the source so you can check it.
When KDP changes its rates, the tools are updated and each page shows when its numbers were last checked.