Ten questions on royalties, pricing and the rules that decide what your book earns. Answer one at a time. At the end you will see your score and the explanation for every answer, so even a wrong answer teaches you something useful.
Most authors learn KDP's rules by losing money on them: a price one cent too low that halves a paperback royalty, a file size that quietly eats an ebook royalty, a category choice made in a hurry. Ten minutes with questions like these is cheaper. When a question surprises you, the linked tools on this site let you test the real numbers on your own book: try the KDP Royalty Calculator with your price and page count.
Rules referenced are Amazon KDP's published rules for Amazon.com as of 2026. Amazon can change them, so confirm on KDP before you publish.