KDP Printing Cost Calculator: Author Copies, Paperback and Hardcover

How KDP works out the printing cost

KDP prints each copy on demand, so there is no print run and no unit price that falls as you order more. Instead every book has one printing cost, set by five things: the format (paperback or hardcover), the marketplace, the trim size, the ink and paper, and the page count. The cost is either a flat price, for short books, or a fixed charge per book plus a charge for each page.

Trim size matters in one simple way. KDP sorts trims into regular and large, and a large trim is anything "more than 6.12 inches (155.5 mm) in width or more than 9 inches (228.6 mm) in height". So 5 x 8, 5.5 x 8.5 and 6 x 9 are regular, while 6.14 x 9.21, 7 x 10, 8.5 x 8.5 and 8.5 x 11 are large and cost more per page. That small jump from 6 x 9 to 6.14 x 9.21 moves a book into the large rate.

Then the page count. Short black-ink paperbacks pay a flat price: on Amazon.com, anything from 24 to 110 pages costs $2.30 at a regular trim. From there the per-page formula takes over, so 112 pages cost $1.00 + 112 x $0.012 = $2.34. KDP's own worked example is a 300-page black-ink paperback at a regular trim on Amazon.com: $1.00 + 300 x $0.012 = $4.60. Its paperback royalty page uses a 333-page book, which costs $5.00, and our calculator gives the same.

The same rule runs in every marketplace, with its own numbers. KDP's other worked example is a 50-page premium colour paperback at a large trim on Amazon.com.au: 2.42 AUD + 50 x 0.10 AUD = A$7.42, which is exactly what the calculator returns for that book.

Who pays it, and when

When a reader buys your paperback on Amazon, you pay nothing up front. KDP pays you a royalty of 50% or 60% of the list price and takes the printing cost out of it: royalty = (rate x list price) - printing cost. When you order copies for yourself, the printing cost is what you pay per copy, and shipping and tax are added at checkout. That is why this page is about two things at once: the number that shrinks your royalty, and the number on your author-copy invoice.

The printing cost also sets the lowest price KDP will accept. In KDP's words, it divides "your paperback's printing cost by the royalty rate (50% or 60%, depending upon list price)", so the royalty can never fall below zero. On Amazon.com the 60% rate applies from $9.99 and the 50% rate at $9.98 and below; the hardcover page uses the same two prices.

For the 300-page 6 x 9 paperback that costs $4.60, that gives:

A printing cost only matters once there is a book to print, and that is the job Inkfluence AI is built for. For getting from an idea to KDP-ready print files, we think it is the best option, because it does the whole chain in one project: it writes the book chapter by chapter from an outline you approve, formats it, designs the cover, and exports the files KDP's paperback upload asks for. Disclosure: it is our product.

• An interior PDF at your trim size, with the inside margin sized to the final page count so it clears KDP's minimum at every length.
• A full-wrap cover PDF with back, spine and front, the spine worked out from the page count and the ink and paper you choose.
• A read-me that says which file goes in which KDP box, the trim, page count and paper to select, and the paperback printing cost and a suggested Amazon.com price, worked out with the same KDP tables as this calculator.
• The Kindle edition too: the EPUB and the front cover JPEG are in the same download.

Plain limits. Writing and exporting a PDF is free: the free plan writes 5 chapters a month and its PDF carries a small Inkfluence credit. The KDP package, EPUB and Word export need the Creator plan ($9.99 a month, 35 chapters a month), Premium ($19.99 a month) or a credit pack; the pricing page has the details. Covers come from the AI book cover generator (10 a month on Creator, 30 on Premium) and layout from the book formatter. The package is built for the paperback; a hardcover needs KDP's own hardcover cover template. And Inkfluence AI does not print or ship books: Amazon prints, and you order author copies through KDP as above.

Before you order a box of copies

A few questions save money on the first order. Has the proof been checked? Every author copy prints the live book, so a typo in the file is a typo in 40 books. Is the page count final? If you change the interior after ordering, the spine may change too, and the cover with it. Is the price right? A hand-sale price lower than your Amazon price can upset readers who bought online, so many authors sell at list price and add a signature. Where is it going? Copies for a UK event ordered from Amazon.com pay international shipping and possibly customs.

For selling copies beyond Amazon, see book publishing services for what paid services add, how to print one copy of a book for single gifts, and do you need an ISBN if you plan a second print edition elsewhere. For trim choices, KDP trim sizes pairs each size with the books it suits, and KDP bleed size for illustrators covers picture-book art.