KDP interior template and margin calculator

With no bleed, the page size is the trim size you chose: an 8.5 × 11 in book is an 8.5 × 11 in page. With bleed, KDP asks for 0.125 in more width and 0.25 in more height, because the extra 0.125 in is on the outside edge, the top and the bottom (never on the inside edge): 8.5 × 11 becomes 8.625 × 11.25 in, and 6 × 9 becomes 6.125 × 9.25 in. Pick your trim size and the tool gives you the exact size in inches, millimetres, PDF points and pixels at 300 dpi. Every page must be the same size, one page per PDF page (no spreads).

Top, bottom and outside margins are at least 0.25 in without bleed and at least 0.375 in with bleed (measured from the edge of the page file, so 0.25 in inside the trim line either way). The inside margin, called the gutter, depends on the page count: 0.375 in for 24 to 150 pages, 0.5 in for 151 to 300, 0.625 in for 301 to 500, 0.75 in for 501 to 700 and 0.875 in for 701 to 828. These are minimums, and KDP's page says they do not have to be equal. The tool draws them on a template and keeps your pictures inside them.

The gutter is the inside margin, the strip next to the spine. A thicker book curls more into the binding, so KDP asks for more room as the page count rises. It is counted on the pages KDP sees, so in a one-sided book the blank backs count: 76 pictures with a blank page behind each are 152 pages, and the inside margin steps up from 0.375 to 0.5 in. The tool counts it that way.

Only if a picture or background should reach the edge of the page. KDP says that if even one page needs bleed, the whole file is set up with bleed. A normal coloring page with white around the picture needs none, and a no-bleed file is simpler: the page is the trim size and the picture stays inside the margins. If you do choose bleed, KDP only supports it in a PDF.

There is no single right size. KDP's paperback table has 16 trim sizes and you can enter a custom size from 4 to 8.5 in wide and 6 to 11.69 in tall. Many coloring and activity books use 8.5 × 11 in or 8.5 × 8.5 in; 6 × 9 in is the US default for text books. Larger trims (over 6.12 in wide or over 9 in tall) are priced differently by KDP. The page limit depends on the trim and the paper: for 8.5 × 11 in it is 24 to 590 pages on white paper and 24 to 550 on cream.

KDP's help lists the usual causes. The page size does not match the trim size you chose in the book's setup, or it was not enlarged for bleed (0.125 in wider, 0.25 in taller). Pictures meant to reach the edge do not extend 0.125 in past the trim line. Or something sits inside a margin. This tool sets the page size and the margins from KDP's published numbers and keeps your pictures out of the margins. The page size matches your setup in KDP as long as you choose the same trim size and bleed setting there, and the full-bleed option crops a picture to cover the whole page including the bleed. KDP's own previewer has the last word: it lists what it found.

For a coloring book it is the usual choice. With one-sided pages every picture gets a blank page behind it, so marker ink cannot show through onto another picture. Page 1 is a right-hand page, so the pictures land on right-hand pages when the book starts with a picture; a blank first page, or a blank page you add, moves the pictures after it onto left-hand pages. Either way each picture has a blank page on the other side of its sheet, and the tool shows which side your pictures are on. The cost is double the page count, and the printing cost KDP charges rises with the page count (a fixed cost plus a per-page cost; the bleed setting does not change it), so use its Printing Cost & Royalty Calculator on the real count. KDP counts those blank pages, and allows no more than 4 blank pages in a row at the start or middle of a book and 10 at the end; alternating blanks are well inside that. The tool offers both ways.

KDP asks for at least 300 dpi, calls anything under 200 dpi low resolution, and advises no more than 600 dpi. The dpi is the picture's pixels divided by the inches it prints at, so it depends on the page: 2550 × 3300 pixels printed 7.875 in wide is 324 dpi. The tool shows every page's real dpi, warns under 300, and flags under 200. Making the picture bigger in software does not add detail. A picture over 600 dpi is brought down to 600 dpi at its printed size, which you can switch off.

24. KDP rounds an odd count up to an even number, so the tool adds a blank last page to an odd book rather than leave it to KDP. The maximum depends on the trim size and the paper in KDP's table (828 is the most any paperback can have, 590 for 8.5 × 11 in on white). For a custom size KDP's pages list no page limit, so the tool does not make one up: it checks 24 and 828 and tells you to read the limit in KDP when you set the size up. Standard color ink needs at least 72 pages at every size KDP lists.

It sets the page size and margins from KDP's published numbers, keeps each picture inside the margins (or crops it to the bleed), flattens transparency onto white, counts the pages, checks the blank-page runs and shows each picture's dpi. The PDF it writes is only your pictures and blank pages: no document information, no annotations, no bookmarks, nothing KDP asks you to remove, and no text, so there are no fonts to embed. KDP can still reject a file for reasons only its previewer sees, for the content itself, or for problems in the pictures. A picture that has its own margins built in is still scaled to fit inside the safe area. Look at the file in KDP's previewer before you publish.

It is not made or approved by Amazon. It uses the numbers KDP publishes and says which help page each came from. Your pictures are read, placed and written into the PDF in your browser, and saved from memory on your computer. Nothing is uploaded.