JSFiddle - React, Tailwind, and code Playground

HTML

<table>
  <tr>
    <td>Click to show cellIndex</td>
    <td>Click to show cellIndex</td>
    <td>Click to show cellIndex</td>
    <td>Click to show cellIndex</td>
 </tr>
</table>

CSS

td {border: 1px solid black;padding:10px;}

JavaScript

var tds = document.querySelectorAll('td');
for(var i = 0, len = tds.length; i < len; i++) {
	tds[i].addEventListener('click', function(e){
  	var td = this || (e || event).target;
		alert(td.cellIndex)
  });
}