[JSWolf]

Originally Posted by roddy20

And Amazon’s kindlegen uses mobi, too

The .mobi that Kindlegen makes is a dual-format file. It included KF8 (AZW3) and Mobi in one file. If the Kindle in use cannot use KF8, it uses the Mobi and if it can use KF8, that's what it uses.

With calibre, you should never convert o Mobi unless you have a K1, K2, or KDX/KDXG.