JSFiddle - React, Tailwind, and code Playground

HTML

<textarea id="myData" onBlur="getWordCount();">Some text thats entered on the page</textarea>

<div id="count"></div>

JavaScript

function getWordCount() {
 var myString = document.getElementById("myData").innerHTML;
 document.getElementById("count").innerHTML = myString.split(" ").length;
}