How to Convert Images for Kindle E-Books

Publishing a Kindle e-book means your images will be displayed on screens ranging from 6-inch e-ink readers to 10-inch tablets to phone apps. Amazon's Kindle Direct Publishing platform has specific image requirements for both cover images and interior illustrations. Getting these wrong results in rejected uploads, blurry covers, or bloated file sizes that increase your delivery costs.

The key challenge is balancing quality with file size. Amazon charges a delivery fee based on your e-book's file size (for books priced in the 35% royalty tier), so unnecessarily large images eat directly into your earnings. At the same time, images that are too small or too compressed look terrible on high-resolution tablet screens.

This guide covers the exact specifications for Kindle cover images, interior illustrations, and the conversion steps to meet Amazon's requirements.

Step-by-Step Instructions

  1. Understand Amazon's Image Specifications

    Kindle cover images must be at least 1000 pixels on the longest side, with 2560 by 1600 pixels recommended for best quality. The aspect ratio should be 1.6:1 (height to width). Interior images should be at least 300 pixels on the longest side but no more than 5 million total pixels. Both covers and interior images must be JPG or PNG format. Amazon rejects TIFF, BMP, and other formats.

  2. Convert Your Cover Image to JPG

    For cover images, JPG at quality 90 to 95 provides the best balance of quality and file size. Amazon compresses images further during processing, so starting with high quality preserves detail through their pipeline. Ensure your cover is exactly 2560 by 1600 pixels at a 1.6:1 aspect ratio. If your source image is in PNG, HEIC, or another format, convert it to JPG before uploading.

  3. Prepare Interior Images

    Interior illustrations, charts, and photographs should be saved as JPG at quality 80 to 85 for photographs and PNG for line art, diagrams, or images with text. PNG preserves sharp edges on text and line art that JPG compression would blur. Keep each interior image under 127KB if possible to minimize the delivery cost impact.

  4. Optimize File Sizes

    Amazon charges delivery fees based on total file size for many pricing tiers. Every megabyte counts. For interior photographs, JPG at quality 80 is usually sufficient since e-ink displays have limited contrast range anyway. For line art and diagrams, PNG with indexed color (8-bit instead of 24-bit) dramatically reduces file size while maintaining sharpness. Resize large images to the minimum dimensions that still look good.

  5. Use sRGB Color Space

    All Kindle images must be in sRGB color space. Images in Adobe RGB, ProPhoto RGB, or CMYK will display with incorrect colors on Kindle devices. If your source images were created in a different color space, convert them to sRGB before saving. Most consumer cameras and phones already shoot in sRGB, but images from professional photography workflows may use wider gamuts.

Cover Image Best Practices

Your cover is the single most important marketing asset for your e-book. On Amazon's search results, covers display as tiny thumbnails around 150 by 100 pixels. Your design must be readable and compelling at that size. After conversion, view your cover at thumbnail size to verify that the title text is legible and the main visual element is recognizable.

Amazon recommends 2560 by 1600 pixels as the ideal cover size. This accommodates high-resolution tablets without being excessively large. The cover file should be under 50MB. Use JPG format unless your cover has transparency (very rare for book covers), in which case use PNG.

E-Ink vs Tablet Display Differences

Kindle e-ink devices display in 16 shades of gray (older models) or 16-level grayscale with higher resolution on newer Paperwhite models. Color images are automatically converted to grayscale on these devices. When preparing images for books likely to be read on e-ink, verify that your images still work in grayscale. High-contrast images with clear boundaries look best on e-ink.

Kindle Fire tablets and the Kindle phone app display full color. If your book is primarily consumed on tablets (cookbooks, children's books, photography books), optimize for color. If it is primarily text with occasional illustrations (novels, non-fiction), optimize for grayscale readability.

Convert with imageconvert.co

Need to convert your cover design from PNG or HEIC to JPG? imageconvert.co handles the conversion entirely in your browser. Your unpublished book cover stays completely private on your device. No upload, no server processing, no risk of your design being seen by anyone else.

Frequently Asked Questions

What image format does Kindle accept for cover images?

Amazon Kindle Direct Publishing accepts JPG (JPEG) and PNG for cover images. JPG is recommended for most covers because it produces smaller files with excellent quality. Use PNG only if your cover requires transparency, which is very rare for book covers.

What size should a Kindle book cover be?

The ideal Kindle cover size is 2560 by 1600 pixels with a 1.6:1 height-to-width aspect ratio. The minimum requirement is 1000 pixels on the longest side. Amazon recommends 2560x1600 for the best display quality across all Kindle devices and the Amazon store.

Do Kindle interior images need to be a specific format?

Interior images should be JPG for photographs and PNG for line art, diagrams, and images containing text. JPG works well for photos with smooth gradients, while PNG preserves the sharp edges that text and line art require.

Does Amazon compress my images further after upload?

Yes, Amazon applies additional compression during the e-book build process. This is why you should start with high-quality images (JPG quality 85-95) so the final result after Amazon's compression still looks good. Starting with low-quality images results in visible compression artifacts after Amazon's processing.

Convert PNG to JPG for your Kindle cover

Convert HEIC photos to JPG

Related Reading