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AZW3 (Kindle)

AZW3, also called Kindle Format 8 (KF8), is Amazon’s ebook format that succeeded MOBI on Kindle devices. It supports richer formatting and layout than MOBI and may carry Amazon DRM that ties a book to your Kindle account.

Files & formatsGeneral

AZW3 (Kindle)

Also known as: .azw3 file, Kindle Format 8, KF8

AZW3, also called Kindle Format 8 (KF8), is Amazon’s ebook format that succeeded MOBI on Kindle devices. It supports richer formatting and layout than MOBI and may carry Amazon DRM that ties a book to your Kindle account.

  • Amazon’s Kindle Format 8 (KF8), successor to MOBI
  • Richer layout and typography than MOBI
  • May carry DRM tying it to your Amazon account

What AZW3 is

AZW3 is Amazon’s Kindle Format 8 (KF8), introduced with the Kindle Fire. It builds on web standards to allow better typography, embedded fonts, and more precise layout than the older MOBI format.

Books bought from the Kindle Store often arrive as AZW3 (or the newer KFX) and can include DRM, which restricts them to the Amazon account that purchased them. DRM-free AZW3 files are not locked this way.

Opening and converting AZW3

Kindle apps and devices open AZW3 natively. Tools like Calibre can open and convert DRM-free AZW3 files to EPUB or PDF for use on other readers.

Like other ebook formats, AZW3 files are mostly compact text. Size grows with embedded images and fonts rather than with the amount of text.

Related terms

Keep reading the reference.

Files & formatsMOBI (Kindle ebook)MOBI is an ebook format originally from Mobipocket that Amazon adopted for early Kindle devices. It holds reflowable book text with chapters and basic formatting, but Amazon has retired it in favor of newer Kindle formats and no longer accepts MOBI uploads.GeneralFiles & formatsEPUBEPUB is the open standard format for ebooks. It is a ZIP package of HTML, CSS, and images, and its text reflows to fit any screen size — unlike a PDF, which keeps a fixed page layout. Most e-readers except Amazon Kindle support it natively.GeneralFiles & formatsPDFPDF (Portable Document Format) is a fixed-layout document format that looks the same on any device. Most PDFs are small, but scanned documents and image-heavy files can grow large, and they accumulate quietly in Downloads and the Files app.GeneralCloud & backupEnd-to-end encryptionEnd-to-end encryption (E2EE) scrambles data so only your devices hold the keys to read it — not even the service storing it can. It protects messages, backups, and cloud files, but means a lost key can make data unrecoverable.General