Free tool
KDP spine width and royalty calculator
Enter the page count, trim size and price of your paperback. The calculation shows the spine width, the printing cost and what you keep per sale.
Result
- Spine width
- 0.450 pol (11.44 mm)
- Printing cost
- US$ 3.40
- Royalty rate
- 60%
- You keep per sale
- US$ 2.59
- Minimum price
- US$ 6.80
Values from KDP help, checked on October 17, 2026; KDP may change the table. Taxes, expanded distribution and hardcovers are not included. For the official figure, use the KDP calculator.
Frequently asked questions
How does KDP calculate the spine width?+
It is the page count times the thickness of one sheet of paper: 0.002252 inch on white paper, 0.0025 on cream, 0.002347 on premium color and 0.002252 on standard color. KDP also has its own calculator, which covers hardcovers.
How is the royalty of a paperback calculated?+
KDP pays the rate times the list price, minus the printing cost. On Amazon.com the rate is 60% for prices of US$9.99 and up and 50% below that. Expanded distribution, which pays 40%, is not part of this calculation.
How much does it cost to print a book on KDP?+
In black and white on Amazon.com, up to 110 pages the cost is flat (US$2.30 in regular size); above that, US$1.00 plus US$0.012 per page. A 200-page book costs US$3.40. Color costs more, and so does the large size.
Does amazon.com.br sell print books?+
No. KDP states that amazon.com.br does not support print distribution. That is why the calculation is in dollars, for the stores that print on demand.
CoAuthor builds the full cover with the spine already calculated
The account is free. The book costs from about US$ 7.70 (R$ 39, paid once, with no monthly fee). You are charged in Brazilian reais; the dollar figure uses the October 17, 2026 rate, about R$ 5.08 per US$ 1.