JSFiddle - React, Tailwind, and code Playground

HTML

<table id="tbl">
  <tr>
    <td>Cell 1</td>
    <td>Cell 2</td>
  </tr>
</table>
<button onclick="calc()">Calculate Offset Width</button>

<div>Cell 1 offsetWidth: <span id="c1offWidth"></span></div>

JavaScript

$(function() {  
    $('button').click(function() {  
        var the_width = $('#tbl tr:eq(0) td:eq(0)').outerWidth();
        $('#c1offWidth').html(the_width);  
    });
});