Free tool · Covers & interior pictures

Image DPI Checker for Print Books

Find out if your picture is sharp enough to print. Pick your picture and where it will print, and see its real DPI at that size. Your picture stays on your device.

Your picture (JPG or PNG)

Where will it print?

Print width (inches)

Print height (inches)

—Resolution at this print size

—Your picture's size in pixels

—Biggest it can print at 300 DPI

Pick a picture to check. It stays on your device; nothing is uploaded.

One picture checked. What about every picture in your book?

SparkPrep checks every image on your cover and every interior page at the size it will actually print, and flags the blurry ones before the printer does. It also checks bleed, fonts, color and ink.

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Why 300 DPI matters for print

DPI (dots per inch) is how many pixels of your picture land in each printed inch. Screens look fine at 72 to 150, but paper shows every missing pixel. Printers ask for 300 DPI at the size it prints. A picture that looks sharp on your phone can still print blurry on a cover.

The "DPI" number in your file doesn't matter. Pixels do.

A photo can say "300 DPI" in its settings and still be too small. What counts is the number of pixels compared to the printed size. To print 6" wide at 300 DPI you need 6 x 300 = 1,800 pixels across. This checker does that math for you.

Pixels you need for common covers (300 DPI)

Book size	Front cover with bleed	Pixels needed
5" x 8"	5.125" x 8.25"	1,538 x 2,475
5.5" x 8.5"	5.625" x 8.75"	1,688 x 2,625
6" x 9"	6.125" x 9.25"	1,838 x 2,775
8.5" x 11"	8.625" x 11.25"	2,588 x 3,375

A full wrap cover (back, spine and front) needs more: use the KDP cover calculator to get its pixel size.

What to do if your picture is too small

Find the original, full-size file (not one saved from email, a website or social media, which shrink pictures).
Buy or download the largest size from the stock photo site.
Print it smaller. The checker shows the biggest size that still reaches 300 DPI.
Simply changing the DPI number in Photoshop without adding pixels does not fix it.

Want every picture checked at once?

SparkPrep checks your whole cover and every interior page against your printer's rules, including image resolution, bleed, fonts, color and ink. It explains every problem in plain English and fixes what it can for you.

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Quick answers

What DPI does KDP require?

KDP recommends 300 DPI for images in print books and warns about images below that in its previewer.

How do I check the DPI of an image?

Divide the picture's width in pixels by the width in inches it will print. 1,800 pixels printed 6 inches wide is 300 DPI. This free checker does it for you.

Does this tool upload my picture?

No. The picture is read in your own browser and never leaves your device.

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SparkPrep is an independent tool and is not affiliated with Amazon KDP, IngramSpark, Barnes & Noble Press or Lulu. Always check your printer's own help pages before you upload.