JSFiddle - React, Tailwind, and code Playground

HTML

<table>
    <tr>
        <td>short</td>
        <td>longer</td>
        <td>the longest cell ever seen on the surface of the earth</td>
    </tr>
</table>

JavaScript

var max = 0,
    $cells = $('td');

$cells.each(function () {
    var width = $(this).width();
    max = max < width ? width : max;
});

$table = $cells.closest('table');

if ($table.width() < max * $cells.length) {
    max = 100 / $cells.length + '%';
}

$cells.each(function () {
    $(this).width(max);
});