JSFiddle - React, Tailwind, and code Playground

HTML

<p><input type="text" id="ti" size="30"></p>

<p id="output"></p>

JavaScript

var inp = document.getElementById("ti");
		
		inp.addEventListener("keydown", onKeyDown);
		
		function onKeyDown(e) {
			if (window.event) {
				var key = window.event.keyCode;
			} else {
				var key = e.keyCode;
			}
			document.getElementById("output").innerHTML +=  String.fromCharCode(key);
		}