JSFiddle - React, Tailwind, and code Playground
HTML
<body>
<img id="im" src="https://s-media-cache-ak0.pinimg.com/736x/dc/0e/27/dc0e27bb52ee71fba9779e6e46c6ec21.jpg" onload="m(this);" />
<script>
function m(t)
{
//var t = document.getElementById("im");
alert(t.naturalWidth + " " + t.naturalHeight);
t.height = t.naturalHeight;
t.width = "200";
}
</script>
</body>