Free tools
KDP calculators, no signup
Small, honest tools for self-publishers. Formula estimates are labelled as estimates, ranges are real ranges, and where no trustworthy number exists we say so instead of inventing one.
Amazon BSR → Sales Calculator
Turn a Best Sellers Rank into an estimated monthly sales range — honest ranges from the documented industry reference chart, and no invented numbers for non-US marketplaces.
Open the calculator →KDP Royalty Calculator
Paperback royalties with real printing costs and the June-2025 60%/50% tiers across 7 Amazon marketplaces, plus eBook royalties with delivery fees and VAT for the 6 biggest.
Open the calculator →KDP Cover Size Calculator
Spine width and the full-wrap cover canvas in inches and millimetres, straight from Amazon’s published formula — with the page-count rules per paper type, never rounded down.
Open the calculator →Calculators estimate. KDPie decides.
These tools run on public formulas. KDPie runs on real marketplace data — demand, competition and per-market sales signals — and gives every niche a clear verdict.
Try KDPie for $7