Turn a MOBI book into EPUB, free with no sign-up and no upload
This MOBI to EPUB converter is free, needs no sign-up or login, and does not upload your book. The file is read in your browser and the EPUB is created on your device, with no watermark.
MOBI is an older Kindle format, and EPUB is the open format read by almost every e-reader app. People convert to open a book on a non-Kindle device or app, or to keep it in a format that is still widely supported.
Text, headings, links and images are kept, and page layout is simplified. DRM-protected books cannot be converted, and this includes most files bought from Amazon, so only DRM-free MOBI files will work.
- Free
- No sign-up
- Never uploaded
- No watermark
Your files are converted on your device and never uploaded.
How to convert
- Drag your MOBI files onto the page, or use the picker to choose them from your device.
- Choose EPUB as the target format.
- Review the options shown, if any, and confirm the book is DRM-free.
- Press Convert and wait while the files are processed on your own device.
- Check the result, then download a single EPUB file or all of them together as a ZIP.
Features
- Keeps text, headings, links and images
- Page layout is simplified
- DRM-protected books cannot be converted
- Reflowable output for any screen size
- Runs on your device, nothing is uploaded
- No watermark and no sign-up
Supported formats
About the formats
About MOBI
MOBI is an older Kindle format based on the Mobipocket reader. It was superseded by KF8, also called AZW3, and then by EPUB. It can be read here but not created.
About EPUB
EPUB is the open e-book standard, a ZIP of HTML files whose text reflows to fit the screen. Kindle accepts EPUB, for example through Send to Kindle.
DRM and what to expect
DRM locks a book to a store account. Files protected that way cannot be converted, and this tool does not try to get around it.
Complex formatting, such as unusual fonts or heavy styling, is simplified in the EPUB.
Privacy: how it works
- Your MOBI books stay on your device. The page reads each file with the browser's file API, converts it with code running in the tab, and hands the result back as a download. No upload happens, so there is no copy of your file on our servers to protect, delete or leak.
- There is nothing to sign up for and no login. The converter does not ask for an email address, and it does not need to know who you are to do its job.
- You can check the claim yourself: open your browser developer tools, watch the Network tab while a file converts, and you will see no request that carries your file.
- The conversion reads your own file and writes a new one on your device. No copy is stored anywhere else.
Tips
- Check that the book is DRM-free before converting.
- Open the EPUB and look at the table of contents and chapter breaks.
- Expect styling to be plainer than the original.
- Keep the MOBI as a backup.
- AZW3 books from Amazon are usually DRM protected.
- Use the EPUB with any reader app that supports it.
Frequently asked questions
Is it really free?
Yes. There is no price, no trial, no credit card and no watermark added to your results. Ulkaa Tool does the conversion with your own device, so there is no server bill to pass on to you.
Are my files uploaded?
No. Your MOBI books are read and converted inside your browser and are never sent to Ulkaa or to anyone else. The result is created on your device and you save it from there.
Do I need an account?
No. There is no sign-up and no login. Open the page, add your files and convert. An Ulkaa account is not needed for anything on this tool.
Is there a file size limit?
No limit is set by us. The real limit is your device: the conversion uses your own memory and processor, so very large files can be slow, and a very big batch may need to be split into smaller runs.