We recently produced an eBook cover for one of our clients and fortunately they knew which publishing platform they were aiming for, as we soon discovered that there’s very little standardisation in the eBook world. Instead it seems that every publisher/distribution channel has different requirements for the cover art; in terms of image density, dimensions and file size.
So to aid in maintaining good mental health we’ve created this handy guide for sizing your cover art. All ebook cover art should use RGB and never CMYK, it is for screen, after all.
For a ‘generic’ ebook cover the recommendation is to stick to 600 x 800 pixels at 72dpi, but be warned that the Nook has a taller aspect than the others, so a horizontal gutter is recommended. And remember that the dots per inch are primarily for context, the dimensions are the important thing to consider.
[EDIT] We’ve updated the guide to account for the new iPad with its huge resolution. To avoid confusion we’ve also chosen to not display the DPI/PPI, as it’s technically irrelivant.
Find the visual guide below, click on it for the full resolution version: