Capitalize Titles and Headings
Properly capitalize your English post titles, page titles and heading blocks after you type it.
Plugin tag: capitalize
To Title Case
Automatically convert post titles on-the-fly, using Kroc Camen's port of John Gruber's title case.
Capitalize Text Input
Aren't you tired of rewriting the titles of your posts pasted in uppercase?
Title Case
Use To Title Case instead! https://wordpress.org/plugins/to-title-case/