Quick Verdict
Use EPUB when…
Use EPUB for universal ebook distribution — it works on Apple Books, Kobo, Nook, Google Play Books, and most reading apps. EPUB is the open standard.
Use MOBI when…
Use MOBI (or the newer AZW3/KFX) only for Kindle devices and the Kindle app. Amazon's ecosystem requires Amazon's format.
EPUB vs MOBI: Feature Comparison
| Feature | EPUB | MOBI |
|---|---|---|
| Apple Books | Yes — native | No |
| Kobo | Yes — native | No |
| Nook | Yes — native | No |
| Kindle devices | Yes (since 2022 firmware) | Yes — native (deprecated) |
| Kindle app (mobile) | No | Yes |
| Open standard | Yes — W3C/IDPF | No — Amazon proprietary |
| DRM support | Adobe DRM, Apple FairPlay | Amazon DRM |
| Status | Active — EPUB 3 current | Deprecated (Amazon uses KFX/AZW3) |
When EPUB wins
- ✓Apple Books: Yes — native
- ✓Kobo: Yes — native
- ✓Nook: Yes — native
When MOBI wins
- ✓Apple Books: No
- ✓Kobo: No
- ✓Nook: No
Frequently asked questions
Can I read EPUB on Kindle?
Yes — Amazon added EPUB support to Kindle devices and Kindle apps in 2022 via a firmware update. You can send EPUB files to your Kindle via the Send to Kindle service. However, the Kindle app on iOS and Android doesn't support EPUB directly — you need to send via Send to Kindle. For Kindle publishing: use KDP (Kindle Direct Publishing) which accepts EPUB and converts to Amazon's internal format.
How do I convert EPUB to MOBI?
Calibre (calibre-ebook.com, free) is the standard tool for ebook conversion. Add your EPUB to Calibre → right-click → Convert Books → set output format to MOBI → OK. Calibre handles EPUB to MOBI (and AZW3, which is better than MOBI for Kindle). Note: MOBI is deprecated — Amazon recommends using KFX or AZW3 instead for Kindle content.
Ready to convert?
Free, browser-based converters — no upload, no signup required.
More comparisons
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