JSFiddle - React, Tailwind, and code Playground

HTML

<input type="text" name="Education[GraduationDate][0]" />
<input type="text" name="Education[GraduationDate][1]" />
<input type="text" name="Education[GraduationDate][2]" />
<input type="text" name="Education[GraduationDate][3]" />

JavaScript

$("input").click(function(){
 alert($("[name^='Education[GraduationDate]']").index(this));
});