JSFiddle - React, Tailwind, and code Playground

HTML

<table>
<tbody>
<tr><td>Something</td><td>Something</td></tr>
<tr><td>Something</td><td><span id='a13113'>20150924</span></td>
</tbody>
</table>

JavaScript

function formatForDate(id) {
        var el = document.getElementById(id);
        var dateStr = el.innerHTML.trim();
        var year = dateStr.substr(0,4);
        var month = dateStr.substr(4,2);
        var day = dateStr.substr(6,2);
        el.innerHTML = day + '/' + month + '/' + year;
        console.log(month);
    }

    formatForDate('a13113');