Print Resolution (DPI) Calculator

Check whether an image is sharp enough for your book cover or interior, or find the pixel size you need for a given print size.

The formula

pixels needed = print size (inches) × DPI
effective DPI = image pixels ÷ print size (inches)

When the width and height give different effective DPI (because the image has a different shape from the print area and will be cropped), the lower value is what counts.

Common sizes at 300 DPI

Use	Print size	Pixels
Full-bleed interior page, 6" x 9" book	6.125" x 9.25"	1838 x 2775
Full-bleed interior page, 8.5" x 11" book	8.625" x 11.25"	2588 x 3375
Full wrap cover, 6" x 9", 200 pages, white paper	12.700" x 9.25"	3811 x 2775
Half-page image, 6" x 9" book	4.5" x 3.5"	1350 x 1050

Worked example

You have a 2400 x 3000 pixel illustration and want it as a full-bleed page in an 8.5" x 11" book. With bleed, the page is 8.625" x 11.25". Effective DPI is 2400 ÷ 8.625 = 278 across and 3000 ÷ 11.25 = 267 down. The lower figure, 267 DPI, is below 300, so it may look slightly soft. At 300 DPI the page needs 2588 x 3375 pixels. A cover with extra room for cropping, say 8.75" x 11.25", needs 2625 x 3375.

Print images versus ebook images

Print and screen need different files. A Kindle screen shows a few hundred pixels per inch at most, so an ebook image rarely needs to be wider than about 1,600 to 2,000 pixels, and larger files raise your delivery cost on the 70% royalty. For print, keep the full-resolution original and export at the exact printed size. Line art and text-heavy images such as charts look best at 600 DPI, because hard edges show softness much sooner than photos do.

For the exact canvas size of a paperback cover, including spine and bleed, use the cover size calculator.

Frequently asked questions

What DPI does KDP need?

KDP recommends at least 300 DPI for images in print books and on covers. Images below that may print blurry, and KDP's previewer warns about low-resolution images.

Is DPI the same as PPI?

For this purpose, yes. Strictly, PPI (pixels per inch) describes the image and DPI (dots per inch) describes the printer, but print guidelines use DPI to mean pixels per inch of printed size.

Can I just change the DPI setting in Photoshop?

Changing the number without adding pixels only changes the print size; it doesn't add detail. What matters is the pixel count compared with the printed size, which is what this calculator checks.

Can I upscale a low-resolution image?

Modern AI upscalers can work well for illustrations and photos, but check the result at 100% zoom for artifacts, especially around text and faces.