📌 2025 Update
Amazon now accepts EPUB files! You can email EPUBs directly to your Kindle, and Amazon will convert them automatically. However, MOBI conversion is still useful for USB transfers and older Kindle devices.
Why Convert EPUB to MOBI?
While Amazon now supports EPUB via email, there are still reasons to convert to MOBI:
- USB Transfer: MOBI works directly when copying via USB cable
- Older Kindles: Some older devices prefer MOBI format
- Control: You control the conversion settings
- Offline: No internet required for USB transfers
- Immediate: No waiting for Amazon's conversion
⚠️ Consider AZW3 Instead
For better formatting results, consider converting to AZW3 (Kindle Format 8) instead of MOBI. AZW3 supports more features and produces better-looking ebooks on modern Kindles.
Conversion Methods
Method 1: Online Converter Recommended
The quickest way to convert EPUB to MOBI without installing software.
1 Upload EPUB
Visit our converter and upload your EPUB file.
2 Select MOBI
Choose MOBI as your target format.
3 Convert & Download
Click convert and download your MOBI file when ready.
Method 2: Calibre (Desktop Software)
Calibre offers the most control over conversion settings.
- Download and install Calibre from calibre-ebook.com
- Add your EPUB to the Calibre library
- Select the book and click "Convert books"
- Choose MOBI as output format
- Click "OK" to convert
💡 Calibre Settings Tips
- Output format: Choose "MOBI" or "AZW3" for better quality
- MOBI Output options: Use "old" format for maximum compatibility
- Page Setup: Select your Kindle model
Method 3: Amazon Email (EPUB → Auto Convert)
Send EPUBs to your Kindle email and let Amazon convert automatically.
- Find your Kindle email at Amazon.com → Manage Content & Devices
- Add your sending email to Approved Personal Document E-mail List
- Email your EPUB as an attachment
- Amazon converts and delivers to your Kindle
Pros: Easy, syncs across devices, cloud backup
Cons: Requires internet, you can't control settings
Method 4: Amazon Send to Kindle App
Amazon's official desktop app for sending documents to Kindle.
- Download Send to Kindle from Amazon
- Sign in with your Amazon account
- Drag EPUB files to the app
- Select destination device(s)
- Click "Send"
MOBI vs AZW3: Which to Choose?
| Feature | MOBI | AZW3 |
|---|---|---|
| Format quality | Basic formatting | Rich HTML5/CSS3 |
| Device support | All Kindles | Kindle 2012+ |
| Embedded fonts | Limited | Full support |
| Fixed layout | No | Yes |
| File size | Smaller | Larger |
| Recommendation | Old Kindles | Modern Kindles |
💡 Recommendation
Use AZW3 for Kindle Paperwhite 2 and newer. Use MOBI only for very old Kindle devices (2012 and earlier) or maximum compatibility.
Transferring MOBI to Kindle
USB Transfer (Works Offline)
- Connect Kindle to computer via USB
- Kindle appears as a removable drive
- Open the Kindle drive
- Copy MOBI file to
documentsfolder - Safely eject Kindle
- Book appears in your library
Email Transfer
- Find your Kindle email (xxx@kindle.com)
- Whitelist your sending email address in Amazon settings
- Send MOBI as email attachment
- Book arrives via WiFi
Troubleshooting Common Issues
Problem: "This document appears to be corrupted"
Solution: The EPUB may have issues. Try converting with a different tool, or check if the EPUB opens correctly in other readers first.
Problem: Formatting looks wrong
Solution: Try AZW3 instead of MOBI for better formatting. In Calibre, try adjusting the "Look & Feel" settings.
Problem: Cover doesn't show
Solution: Ensure the EPUB has an embedded cover. In Calibre, you can add/replace covers before converting.
Problem: Book doesn't appear on Kindle
Solution: Make sure you put it in the documents folder (not a subfolder). Try restarting Kindle. Check file isn't DRM-protected.
Problem: Table of contents missing
Solution: Enable "Force use of Auto-generated Table of Contents" in Calibre's conversion settings.
Best Practices for Quality Conversion
- Start with good source: Clean, well-formatted EPUBs produce best results
- Check cover: Ensure your EPUB has a proper cover image
- Verify metadata: Title and author should be correct
- Test on device: Always check the result on your actual Kindle
- Keep original: Save your EPUB, you might need it later
Frequently Asked Questions
Q: Can I convert DRM-protected EPUBs?
No, DRM-protected files cannot be converted. You can only convert DRM-free EPUBs that you own.
Q: Is MOBI the same as AZW?
They're similar. AZW is essentially MOBI with Amazon DRM. Unprotected MOBI files work on all Kindles.
Q: Should I still use MOBI in 2025?
For most users, sending EPUB via email or using AZW3 is better. MOBI is mainly for older devices or USB transfers.
Q: Why is my converted file larger than the original?
MOBI files can be larger due to compatibility structures. AZW3 is usually more efficient.
Conclusion
Converting EPUB to MOBI gives you full control over your ebook library and ensures compatibility with all Kindle devices. While Amazon's email system now accepts EPUBs, local conversion remains valuable for USB transfers and older devices.
For best results on modern Kindles, consider AZW3 format instead of MOBI. Start with our free online converter for quick results!