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“Kindle e-book format” can mean a manuscript file uploaded to Kindle Direct Publishing (KDP) or a personal document sent to a Kindle library. The supported files differ by workflow: for KDP, use EPUB or KPF for reflowable or fixed-layout books, and DOCX for reflowable books. For personal documents, Send to Kindle accepts EPUB among other file types. MOBI is no longer accepted for new KDP uploads.
First decide whether you are publishing or transferring a document
KDP manuscript formats are for turning a book into a title published through Amazon. Send to Kindle formats are for delivering a personal document to your own Kindle library. EPUB appears in both workflows, but the rules are not interchangeable.
| Workflow | Formats and guidance |
|---|---|
| Publish through KDP | EPUB or KPF can be used for reflowable and fixed-layout ebooks. DOCX is an option for reflowable ebooks. Follow Amazon’s KDP manuscript format guidance and validate the result before publishing. |
| Send a personal document to Kindle | Amazon’s Send to Kindle support lists EPUB, PDF, DOC/DOCX, TXT, RTF, HTML and image types among accepted formats. This transfers a document to a personal library; it does not publish a book through KDP. |
Which file formats can you upload to KDP?
Amazon’s KDP guidance supports EPUB 2.0 and EPUB 3.0 files that meet its specifications. KPF is the Kindle Create package format Amazon recommends for its publishing workflow. DOCX is commonly used as a source for reflowable books; most DOC/DOCX files convert, though complicated formatting may not carry over cleanly.
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| Format | KDP use | Practical note |
|---|---|---|
| EPUB | Reflowable or fixed-layout ebook | Use a compliant EPUB 2.0 or 3.0 file and inspect it in Kindle Previewer. |
| KPF | Reflowable or fixed-layout ebook | Export from Kindle Create; Amazon identifies KPF as its preferred publishing path. |
| DOCX | Reflowable ebook | Useful as a manuscript source, but formatting may convert poorly if the document is complex. |
| MOBI | Not accepted for new KDP ebook uploads | Amazon ended reflowable MOBI upload support on August 1, 2021, and fixed-layout MOBI upload support effective March 18, 2025. Existing published titles do not need changes unless you update them. See Amazon’s MOBI support FAQ. |
Choose reflowable or fixed layout based on the book
Reflowable: text that adapts to the reader
In a reflowable ebook, text adjusts to screen size and readers can change text settings such as font size. This is usually the better fit for novels and other text-heavy books, and it supports more reader controls and accessibility features. Amazon’s format comparison explains the differences.
#1 Best Overall
- Light and compact - With adjustable brightness, high contrast ratio, and fast page turns.
- Effortless reading in any light - Read comfortably with a 6“ glare-free display, adjustable front light—now 25% brighter at max setting—and dark mode.
- Escape into your books - Tune out messages, emails, and social media with a distraction-free reading experience.
- Read for a while - Get up to 6 weeks of battery life on a single charge.
- Take your library with you – 16 GB storage holds thousands of books.
Fixed layout: pages that preserve a designed arrangement
Fixed layout keeps page elements in a set arrangement, which can suit image-heavy children’s books or coffee-table books where the design matters. The trade-off is that some fixed-layout formats restrict text selection, font adjustment or screen-reader support. Print Replica is not compatible with Kindle E Ink readers and lacks key accessibility features, including text resizing and screen-reader compatibility.
Amazon converts a Kindle book into one format, so choose the layout that preserves the content’s essential features rather than expecting every print design or interactive element to survive unchanged.
Rank #2
- Light and compact - With adjustable brightness, high contrast ratio, and fast page turns.
- Effortless reading in any light - Read comfortably with a 6“ glare-free display, adjustable front light—now 25% brighter at max setting—and dark mode.
- Escape into your books - Tune out messages, emails, and social media with a distraction-free reading experience.
- Read for a while - Get up to 6 weeks of battery life on a single charge.
- Take your library with you - 16 GB storage holds thousands of books.
Use Kindle Create and Previewer to check the result
- Create or import the book in Kindle Create. Kindle Create exports KPF and EPUB. KPF is Amazon’s preferred KDP route. EPUB export is limited to reflowable books and does not support every Kindle feature, including image bleeds, drop caps and chapter-start imagery. See Kindle Create guidance.
- Open the file in Kindle Previewer. Previewer can open EPUB, HTM/HTML, XHTML, OPF, KPF, DOC and DOCX files. Its DOC/DOCX opening support is limited to English-language content. Amazon says Previewer shows appearance across Fire tablets, Kindle apps and Kindle E-readers; see its Kindle Previewer help page.
- Check the actual reading experience. Review chapter starts, images, spacing, navigation and text resizing on the available device views. Fix conversion problems in the source file or layout and preview again before publishing.
What devices can read Kindle books?
Kindle format is not a requirement to own a Kindle e-reader. Amazon lists its cited KDP manuscript formats as compatible with Kindle E Ink readers, Fire tablets and Kindle apps, so readers can use an app as the destination. The cited Amazon guidance primarily reflects US English-language KDP documentation and does not establish a complete country-by-country or device-by-device compatibility matrix.
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Best Value
- Our fastest Kindle Paperwhite ever – The next-generation 7“ Paperwhite display has a higher contrast ratio and 25% faster page turns.
- Upgrade your reading experience – The Signature Edition features an auto-adjusting front light, wireless charging, and 32 GB storage.
- Ready for travel – The ultra-thin design has a larger glare-free screen so pages stay sharp no matter where you are.
- Escape into your books – Your Kindle doesn’t have social media, notifications, or other distracting apps.
- Adapts to your surroundings – The auto-adjusting front light lets you read in the brightest sunlight or late into the night.
Rank #4
- Our fastest Kindle Paperwhite ever – The next-generation 7“ Paperwhite display has a higher contrast ratio and 25% faster page turns.
- Ready for travel – The ultra-thin design has a larger glare-free screen so pages stay sharp no matter where you are.
- Escape into your books – Your Kindle doesn’t have social media, notifications, or other distracting apps.
- Battery life for your longest novel – A single charge via USB-C lasts up to 12 weeks.
- Read in any light – Adjust the display from white to amber to read in bright sunlight or in the dark.
Rank #3
- Our fastest Kindle Paperwhite ever – The next-generation 7“ Paperwhite display has a higher contrast ratio and 25% faster page turns.
- Ready for travel – The ultra-thin design has a larger glare-free screen so pages stay sharp no matter where you are.
- Escape into your books – Your Kindle doesn’t have social media, notifications, or other distracting apps.
- Battery life for your longest novel – A single charge via USB-C lasts up to 12 weeks.
- Read in any light – Adjust the display from white to amber to read in bright sunlight or in the dark.
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
