Calibre
Calibre is a free, open-source ebook manager with metadata editing, library organization, readers, device transfer, and format conversion.
Limitations: Conversions cannot reliably preserve every layout, and DRM-protected books are not supported for ordinary conversion. Respect copyright and keep source files.
Why it is useful
Calibre is a free, open-source ebook manager with metadata editing, library organization, readers, device transfer, and format conversion. This resource is especially useful for Managing ebooks and converting between many unprotected ebook formats. Review the current instructions and limitations from calibre before relying on it for important work.
Limitations
Conversions cannot reliably preserve every layout, and DRM-protected books are not supported for ordinary conversion. Respect copyright and keep source files.