Images look blurry in Kindle ebooks because Amazon compresses every interior image to approximately 96 DPI during its EPUB-to-Kindle conversion, regardless of your source file quality. The fix is to start with images at 300 DPI and at least 1,600 pixels on the longest side, use the right file format for the image type, and accept that some quality loss is unavoidable once the file enters the ebook image resolution pipeline.
- What Ebook Image Resolution Does KDP Actually Require?
- Does Amazon Compress Your Images During Conversion?
- JPEG vs PNG for Ebook Images: Which Format Should You Use?
- How Do Images Look on Kindle E-Ink vs Fire Tablet?
- How to Export and Optimise Images from Word and InDesign
- How Do Other Platforms Handle Ebook Images?
- Frequently Asked Questions
What Ebook Image Resolution Does KDP Actually Require?
KDP recommends a minimum of 300 DPI for all source images, with full-page ebook images ideally sized at 1,200 × 1,800 pixels (a 1:1.5 aspect ratio that matches the standard Kindle screen proportion). The maximum dimensions KDP accepts are 10,000 × 10,000 pixels, and the total uploaded file size cannot exceed 50 MB.
These numbers deserve a closer look. The 300 DPI recommendation refers to the resolution of your source file before upload; it does not mean your image will display at 300 DPI on a reader’s device. According to KDP’s image formatting guidelines, screen-resolution images (72 to 150 DPI) are adequate for digital display, but higher-resolution source files survive the compression pipeline with more detail intact. Starting at 300 DPI gives Amazon’s converter enough pixel data to produce a result that still looks sharp after downsampling.
For images that do not fill the full screen (inline diagrams, charts, or small illustrations), KDP’s reflowable content guidelines recommend that photos occupy roughly 60% of the screen width and images containing text occupy 80%. These are guidelines rather than hard limits, but following them prevents images from rendering too small to read or too large to fit on a single screen.
Does Amazon Compress Your Images During Conversion?
Yes. Amazon compresses every image during the EPUB-to-Kindle conversion process, and the compression is aggressive. Source images at 300 DPI are typically reduced to approximately 96 DPI in the delivered file, with individual images often compressed to around 60 KB regardless of their original size.
This compression is not optional; there is no setting to disable it. Amazon applies it to keep delivery file sizes small (which directly affects both download speed and KDP delivery costs at the 70% royalty rate, where Amazon charges $0.15 per megabyte of the converted file). An image-heavy book with 50 or more interior images can accumulate $1.50 or more in delivery costs per copy sold, which is a meaningful margin hit for a book priced under $5.00.
The practical consequence: you cannot fully control how your images look in the final Kindle file. What you can control is the quality of your input. A 300 DPI JPEG with minimal pre-upload compression will survive Amazon’s pipeline far better than a 72 DPI image that has already been compressed twice. Think of it as giving the converter the best possible raw material to work with, knowing it will degrade the result.
JPEG vs PNG for Ebook Images: Which Format Should You Use?
JPEG is the better default choice for most ebook interior images, particularly photographs, illustrations with gradients, and any image with continuous tones. PNG is better for line art, diagrams, and images with large areas of flat colour, but with an important caveat: KDP automatically converts PNG files to JPEG during processing, so your PNG will undergo lossy compression regardless.
This automatic conversion is why authors sometimes see clean diagrams degrade after upload. A PNG diagram with crisp black lines on a white background converts cleanly to JPEG at high quality, but at the aggressive compression levels Amazon applies, JPEG artefacts (the smudgy halos around sharp edges) become visible. The workaround is to increase the resolution of line-art PNGs to at least 1,600 pixels on the longest side; more pixel data means the JPEG artefacts are smaller relative to the line weight and less noticeable on screen.
For photographs, JPEG at quality 80 to 85 (on a 0 to 100 scale) before upload strikes the right balance. Going higher wastes file size without visible improvement after Amazon re-compresses. Going lower introduces artefacts that compound with Amazon’s own compression pass, producing noticeably muddy results. If you are working in Adobe Photoshop, export using “Save for Web” at quality 80 with the “Progressive” option enabled; in Adobe InDesign, export your EPUB with image quality set to “High” rather than “Maximum” to avoid unnecessarily large files that slow the conversion.
How Do Images Look on Kindle E-Ink vs Fire Tablet?
The same image file renders very differently on Kindle e-ink devices and Fire tablets, and understanding why helps you make better formatting decisions. E-ink Kindles display images in greyscale only, with screen resolutions ranging from 167 PPI on older models to 300 PPI on the current Kindle Paperwhite. Fire tablets display full colour at 171 to 189 PPI, depending on the model.
Colour images lose their intended meaning on e-ink devices because the screen converts them to greyscale. A chart that uses red and green to distinguish two data series becomes two nearly identical shades of grey. If your book relies on colour-coded diagrams, consider adding text labels or pattern fills (hatching, dots, crosshatching) so the information survives greyscale conversion. You can preview your ebook on different devices before publishing to catch these issues before readers do.
The PPI difference also matters. An image that looks sharp on a 300 PPI Paperwhite may appear noticeably softer on a 171 PPI Fire 7 tablet, because the lower pixel density cannot resolve fine detail. This is another reason to start with high-resolution source images: they degrade more gracefully across the full range of devices readers actually use.
How to Export and Optimise Images from Word and InDesign
Microsoft Word applies automatic image compression by default, and this is one of the most common hidden causes of blurry ebook images. When you insert a high-resolution image into a Word document, Word may silently compress it to 220 DPI or lower unless you change the setting. To disable this: go to File > Options > Advanced, scroll to “Image Size and Quality,” and tick “Do not compress images in document.” Set the default resolution dropdown to “High fidelity” or 330 PPI. Do this before inserting images; the setting does not retroactively restore quality to images already compressed.
In Adobe InDesign, the EPUB export dialog controls image quality directly. Under the “Images” panel, set resolution to 300 PPI, format to JPEG, and quality to “High” (which maps to approximately quality 80). Avoid “Maximum” quality; it produces files roughly twice the size for a difference that vanishes after Amazon’s compression pass. For image-heavy books like children’s picture books, keeping individual images under 2 MB before upload helps avoid conversion timeouts.
Authors using Vellum or Atticus for ebook formatting have less direct control over image export settings; both tools handle compression internally. Vellum applies its own optimisation during EPUB generation and generally produces good results if the source images are 300 DPI. Atticus similarly processes images during export. In both cases, the quality of the source file you insert determines the ceiling; neither tool can improve an image that was already low-resolution when imported.
How Do Other Platforms Handle Ebook Images?
Each ebook distribution platform applies its own image processing rules, and a file that looks sharp on one platform may appear differently on another. Understanding these differences matters if you distribute through multiple channels, which is the case for the majority of indie authors who publish across KDP, Apple Books, and Google Play simultaneously.
Apple Books imposes a maximum of 5.6 million pixels per interior image (for example, 2,800 × 2,000 pixels would hit the limit). Apple recommends sizing images at 1.5 times the intended viewing size and specifies a minimum of 300 DPI for cover images. Apple’s compression is generally lighter than Amazon’s; authors with image-heavy books often report that the same file looks sharper on Apple Books than on Kindle.
IngramSpark specifies 300 PPI for colour and greyscale interior images and 600 PPI for line art (black-and-white diagrams, illustrations with no grey tones). These specs apply to both print and ebook files distributed through IngramSpark’s ebook channel. The higher line-art requirement reflects the fact that black-and-white images with sharp edges need more pixel data to avoid visible stair-stepping (aliasing) on screen.
Google Play Books and Kobo both accept standard EPUB 3 files and apply their own processing during ingestion. Neither publishes detailed image-compression specifications in the way KDP and IngramSpark do, but the W3C EPUB 3.3 specification that all these platforms build on requires support for JPEG, PNG, GIF, and SVG as core image types. In practice, starting at 300 DPI and using JPEG for photographs produces acceptable results on all four platforms.
Frequently Asked Questions
Why do screenshots and charts look worse than photos in ebooks?
Screenshots and charts contain sharp edges, thin lines, and small text, all of which suffer visibly from JPEG compression artefacts. Photos, by contrast, are made up of continuous tones and gradients that mask compression. When Amazon converts your EPUB to Kindle format, it applies JPEG compression to every image; the artefacts (blurry halos around edges) are far more visible on a chart with crisp black lines than on a photograph of a landscape. Increasing the resolution of charts and screenshots to at least 1,600 pixels wide reduces this effect.
What is the maximum image file size KDP allows for ebook uploads?
KDP allows individual images up to the 50 MB total file size limit for the entire uploaded EPUB. There is no published per-image file size cap, but images larger than 5 MB often cause conversion slowdowns or failures. Amazon’s internal Kindle format supports images up to 127 KB each after conversion; anything larger is compressed further to fit. Keeping source images under 2 MB each before upload is a practical target that balances quality with reliable conversion.
Can I use SVG images in a reflowable EPUB?
Yes. SVG (Scalable Vector Graphics) is a supported format in the EPUB 3 specification and works well for diagrams, flowcharts, and any computer-generated visual that benefits from resolution independence. KDP’s reflowable content guidelines specifically recommend SVG for computer-generated visuals because the format scales cleanly to any screen size without pixelation. However, SVG support varies by reading app and device; complex SVGs with embedded fonts or filters may not render identically everywhere.
Do ebook images affect my royalty earnings on KDP?
At the 70% royalty rate, KDP charges a delivery fee of $0.15 per megabyte based on the converted file size. A text-only novel typically costs a few cents in delivery. A non-fiction book with 30 interior images might cost $0.60 to $1.00 per copy. A heavily illustrated book with 100+ images could cost $2.00 or more per copy. At the 35% royalty rate, there is no delivery fee. Authors with image-heavy books sometimes choose the 35% rate specifically because the delivery costs at 70% would consume a large portion of their royalty.
How do I check my image quality before uploading to KDP?
Use Kindle Previewer 3 (free from Amazon) to open your EPUB file and inspect how images render on simulated Kindle devices. Pay particular attention to charts, diagrams, and any image containing text. Zoom in to check for JPEG artefacts around sharp edges. Also check on a simulated e-ink device to see how colour images convert to greyscale. If an image looks soft or blurry in Kindle Previewer, it will look the same or worse on an actual device.
Blurry ebook images are frustrating, but they are largely preventable. Start with 300 DPI source files, export at JPEG quality 80 to 85 for photographs, increase the resolution of line art and charts, disable Word’s automatic compression, and test in Kindle Previewer before uploading. The conversion pipeline will always degrade quality to some degree; the goal is to give it enough headroom that the result still looks sharp on the reader’s screen.
