JSFiddle - React, Tailwind, and code Playground

HTML

<span id="foo">123</span>
<br/>
<a href="#" id="go">Go!</a>

CSS

#foo { font-size: 24px; font-weight: bold; font-family: monospace; }

JavaScript

var changeto = 456;

function slotmachine(id) {
    var thisid = '#' + id;
    var $obj = $(thisid);
    $obj.css('opacity', '.3');
    var original = $obj.text();

    var spin = function() {
        return Math.floor(Math.random() * 10);
    };

    var spinning = setInterval(function() {
        $obj.text(function() {
            var result = '';
            for (var i = 0; i < original.length; i++) {
                result += spin().toString();
            }
            return result;
        });
    }, 10);

    var done = setTimeout(function() {
        clearInterval(spinning);
        $obj.text(changeto).css('opacity', '1');
    }, 10000);
}

$('#go').click(function() {
    slotmachine('foo');
});