Are the original chapters kept?

Yes. A KF8 file keeps each of the book’s documents as a separate HTML document inside one flow, so the chapters come out as they were authored rather than being guessed from headings.

Why does the converted book look plainer?

The AZW3 stylesheet is stored in a Kindle-specific layout and is not carried across. The text, structure, images, cover and contents list are; the typography becomes your reader’s.

Can it convert Kindle books bought from Amazon?

Not protected ones. DRM is detected from the file header and the book is refused with an explanation. DRM-free books, your own books and public-domain downloads convert normally.

Can I convert AZW3 to MOBI instead?

Yes — use AZW3 to MOBI for an older Kindle that does not open AZW3.

AZW3 → EPUB

AZW3 to EPUB

AZW3 — Kindle Format 8 — is structurally close to EPUB already: real XHTML documents with real CSS, packed into a Kindle container. That closeness is why this conversion keeps the book’s original chapter divisions rather than guessing at them.

No upload · Files are read in this tab and never sent anywhere

Intake

Drop AZW3 files here

.azw3 and .kf8. A combination file containing both an old MOBI and a KF8 version is detected, and the newer half is the one read.

Output format

EPUB — The open standard. Reflows to any screen, and read by everything except Kindle hardware.

Add a cover page at the frontSome readers show the cover from the metadata alone; others only show it if it is also the first page. Off means the cover is still in the file and still marked as the cover.

Why the chapters come out right

Inside a KF8 file the book’s documents are concatenated into a single flow, each one still beginning with its own <html> tag. Those boundaries are the divisions the book was authored with, so the chapters here are the real chapters — not sections reconstructed from where headings happen to fall.

What is not carried across

The book’s own stylesheet. KF8 stores it in a separate flow in a Kindle-specific layout, and applying it to a rebuilt package would be guesswork. Text, structure, images, the cover and the contents list all come across; the typography becomes your reader’s.

Kindle-internal links — kindle:pos: references into the file’s own positions — are dropped rather than left pointing at a scheme no other reader understands.

Books bought from Amazon

A book downloaded through “Download & transfer via USB” is usually protected. Protection is detected from the header and the file is refused with an explanation — this does not remove DRM and will not try to. Books you have written, bought DRM-free, or downloaded from a public-domain archive convert normally.

Not sure which format you have? Inspect the file — it reports what the bytes actually are, whatever the extension says. Need a file for an older Kindle? AZW3 to MOBI.

Questions

Are the original chapters kept?: Yes. A KF8 file keeps each of the book’s documents as a separate HTML document inside one flow, so the chapters come out as they were authored rather than being guessed from headings.
Why does the converted book look plainer?: The AZW3 stylesheet is stored in a Kindle-specific layout and is not carried across. The text, structure, images, cover and contents list are; the typography becomes your reader’s.
Can it convert Kindle books bought from Amazon?: Not protected ones. DRM is detected from the file header and the book is refused with an explanation. DRM-free books, your own books and public-domain downloads convert normally.
Can I convert AZW3 to MOBI instead?: Yes — use AZW3 to MOBI for an older Kindle that does not open AZW3.