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AZW3 to EPUB Converter
Convert Kindle KF8 books to EPUB for any reader. Runs entirely on your device.
Files never uploaded Works offline Free, no signup No file size limits
How it works
- Drop your AZW3 file into the box above.
- Your browser unpacks the KF8 container and rebuilds it as EPUB – locally, with no server involved.
- Download the EPUB and read it anywhere.
Why “no upload” matters
Every conventional converter site works the same way: your file travels to their server, sits in their queue, gets converted on their hardware, and – you hope – gets deleted afterwards. You can’t verify any of it. The FBI has even warned about free converter sites that use that upload as a way to deliver malware or harvest the documents themselves. Your books are yours; a format change shouldn’t require handing them to a stranger.
ebook.tools removes the question entirely. The converter is delivered to your browser as code and runs on your machine; the file you drop is opened from memory, transformed, and saved back – the network isn’t involved at all. That isn’t a policy promise, it’s an architecture, and you can test it: load this page, switch off your wifi, and convert. It works exactly the same, because there was never anything to send.
AZW3, KF8 and where these files come from
AZW3 is Amazon's "Kindle Format 8" (KF8), introduced with the Kindle Fire in 2011 to replace the ageing MOBI format. Under the hood it's built on the same web technologies as EPUB – HTML and CSS – which is precisely why it converts so well: headings, embedded fonts, drop caps, tables and complex layouts generally survive the trip to EPUB intact. Of the whole Kindle format family, AZW3 gives the highest-fidelity conversions.
Where do AZW3 files come from? Mostly three places: books you sideloaded onto a Kindle over USB, Calibre libraries (Calibre used AZW3 as its preferred Kindle output for years), and old backups of Kindle devices. If you're switching to a Kobo, a Boox, or a reading app on your phone, those files are stranded in a format only Kindles read – converting them to EPUB sets them loose.
The conversion maps KF8's structure directly onto EPUB 3: the spine becomes the EPUB spine, the internal NCX navigation becomes a proper table of contents, cover art and metadata (author, title, series) carry across, and stylesheets are extracted and preserved rather than flattened. Because KF8 and EPUB 3 are such close relatives, there's far less "translation loss" than with old MOBI conversions.
The honest bit: books purchased from the Kindle store carry Amazon DRM, and this tool will not unlock them – we detect DRM and say so plainly rather than emit a corrupt file. What converts cleanly is everything DRM-free: sideloads, Calibre output, technical books from publishers like O'Reilly-style stores, and indie titles sold without locks.