It's a powerful program that can really help folks who have multiple readers or who want to explore new formats. Of course, you can use Calibre to convert other e-book files as well. You can use it on any operation system such as Windows, Mac, Linux or even ChromeBook, as long as you have a web browser.

It doesn't usually take very long, and once you've converted them, you can send them straight to your Kindle from within Calibre by selecting 'Connect/share' from the top right or aiming your device at the correct folder. Neat Reader for Web is an online ePub reader that works on all modern web browsers.

When you're settled, click 'OK' at the bottom right. You have a vast array of options to choose from, but for most EPUBs, you should find the basic setup good enough. To open ePub files in Windows 10, you need an ePub reader, or you can download the EPUB app from Microsoft store.

Calibre should have automatically decided on the MOBI format if you use a Kindle as your primary reader.

Select the EPUB files you want to convert and click 'Convert books' in the top bar.

Add any EPUB files you've got that you want to convert.

From the main screen, you can choose to add books by clicking the large icon in the top left.

When you first run it, Calibre will ask what language you want to use, and to select a folder to use as your e-book library.

Calibre is a free, open-source e-book manager that lets users convert EPUB files to Kindle-readable MOBI files. If you use an e-reader, it's probably a Kindle, which means it can be a pain to use open-source e-book formats like EPUB.

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