MMANA-GAL (the basic edition) is free antenna analysis software.  MM is for Makato Mori, the initial author.  Or maybe it's for Method of Moments, how the software works.  GAL is for some German fellows who translated it and brought it to the non-Japanese speaking world.

Some of its best features are hidden under the tabs for Tools, then HF components.  Here is a section to calculate loading coils, LC matching circuits and three different flavors of stub matches.

If you do antenna designs, you should try it.