The best formats to use for the internal Kindle e-book cover is a JPG or GIF image, 127 KB* size at 300 dpi. This will provide enough clarity for images, particularly for large images, or content with gradient patterns. But you also don’t want the e-book file size to become too large.
*Amazon recommends a a course in miracles “The largest element of almost any Kindle book will be the image content. Inside your book file, the Kindle book format supports JPEG and GIF images up to 127KB in size. Images that are in other formats supported for upload to KDP (such as BMP or PNG), or that exceed this file size requirement, will be automatically recompressed as JPEG files during the conversion process.
Optimizing your images to fit these requirements before uploading to KDP will help decrease the size of your uploaded file. It will also reduce the chance of encountering difficulties in conversion due to large file size.” HOWEVER once the reader has purchased your e-book, the Internal eBook cover is a moot point — they may go and look at your e-book cover, but most do not.
If you choose to upload your Word (.doc) file, and you have embedded images in your content, Kindle Direct Publishing automatically extracts images from the content and replaces them with an HTML img tag. This process converts each image to a separate image file, which becomes a part of your content’s publication package (MOBI)
Note: Images do not display accurately when you preview an uploaded file. For instance, larger images may resize or rotate when previewed. If your book has a lot of images, it can be viewed in color by the Kindle Fire or by readers using our free Kindle apps for PC, Mac, iPad, iPhone, Android, and Windows 7 devices. Otherwise, remember that images on Kindle (with the exception of the Fire) are displayed in 16 shades of gray for great contrast and clarity.
The Product Display Book Cover
The product display cover is the image that resides on the virtual bookshelf in the Amazon Kindle Store. It must be 72 dpi and I recommend a JPG file. I commonly create the product cover from the 600 x 800 Internal book cover. The product image needs to be crisp, sharp, and does not need to be any larger the 127K, however, Kindle Direct Publishing accepts two types of files for product display cover images:
- JPEG, or.jpeg
- TIFF, or.tif(f)
KDP applies additional compression to images when displaying them on its website. For best results, images should be uploaded with minimal compression.
I have found the best size to create your cover is 600 x 800 pixels. This is slightly more square than an 6 x 9 inch book cover. In addition, the product cover is displayed on the Web, so the resolution only needs to be 72 dpi for optimal viewing.
Requirements for the size of your cover art:
- Image dimensions of at least 500 by 800 pixels — 600 x 800 pixels produces a full screen cover image.
- Do not make your image any larger than 2000 pixels on the longest side.
- Save at 72 dots per inch (dpi) for optimal viewing on the web.
Color attracts attention so use color images whenever possible and relevant. The Kindle Fire offer exceptional color clarity, so use color images in your e-book. Although the other Kindle reading devices have a black and white screen, Amazon has Kindle apps for other devices, such as iPhone or PC, which takes advantage of color fonts and images. All images on the Web display using RGB (red, green, blue) color mode, which is the color mode native to the Web and many color screen displays. Combinations of these three colors at varying levels of intensity create over 16 million colors.