Step 1: Attach your EPUB files using the button above or by bring and position.
Step 2: Click the 'Optimize' button to start the optimization.
Step 3: Collect your converted AZW3 files.
EPUB to AZW3 Optimization FAQ
How do I convert a EPUB ebook to AZW3?
+
Upload the EPUB file and the converter repackages it as a AZW3 ebook — same text, chapters, images, and metadata, in the container your target reader prefers. Both EPUB and AZW3 are reflowable, so the conversion is structural, not a re-layout.
Why convert EPUB to AZW3 — aren't they both ebooks?
+
Different readers favor different formats: Amazon devices want the Kindle family, while Apple Books, Kobo, and most others want EPUB. Converting EPUB to AZW3 simply makes your book open natively on the device you actually use.
Will chapters and the table of contents survive EPUB to AZW3?
+
Yes — the navigation structure carries across, so the AZW3 keeps a working chapter list and readers can jump between sections exactly as in the EPUB.
Do cover art and metadata transfer from EPUB to AZW3?
+
Yes — title, author, and the cover image move from the EPUB into the AZW3, so the book appears correctly in your reader's library rather than as an untitled file.
Will my reading position or highlights carry over?
+
No — bookmarks, highlights, and reading position live in your reader app, not in the EPUB file, so they do not travel with a format conversion. The book's content and structure convert; personal annotations do not.
Does DRM stop me converting EPUB to AZW3?
+
Yes — DRM-protected EPUB files are encrypted and cannot be converted. DRM-free EPUB files (your own work, public-domain titles, DRM-free purchases) convert without issue.
Will images and formatting look the same in the AZW3?
+
Embedded images and structural formatting (headings, italics, lists) carry across cleanly. Because both formats reflow, exact line breaks differ by design — that is normal ebook behavior, not a conversion error.
Can I convert a whole shelf of EPUB files to AZW3 at once?
+
Yes — drop multiple EPUB files and each becomes its own AZW3 in parallel, which is the fastest way to migrate a library between reader ecosystems.
Is my EPUB ebook private during conversion?
+
Yes — the EPUB and the resulting AZW3 are processed in isolated workers and deleted within minutes. No human reads the book. See /privacy/.
How long does EPUB to AZW3 take?
+
Usually seconds — the content is repackaged rather than re-rendered, so even a long EPUB converts quickly unless it carries many large images.
Will the AZW3 work on my specific e-reader?
+
Pick the AZW3 format your device documents as native (EPUB for most, Kindle-family for Amazon) and it will open directly. Side-loading instructions vary by device but the AZW3 itself is standards-compliant.
Do I need Calibre or any app to convert EPUB to AZW3?
+
No — the conversion runs on our servers; nothing to install. You only need your e-reader or its app to open the finished AZW3.
