JSFiddle - React, Tailwind, and code Playground

HTML

<div id="wrap"  style="transform: scale(2); width:300;height:300; padding:green 20px solid;">
	<svg id="real" style="border:red 10px solid;" >
		 <rect/>
    </svg>
	</div>

JavaScript

var e = document.getElementById("real");
    var rect = e.getBoundingClientRect(); // rect is dimension after scale

	console.log(e.offsetWidth);
	console.log(e.clientWidth);
	console.log(rect.width);