1,234.01

    <input type="text" value="">
    <script type="text/javascript">
    $('input').blur('input propertychange', function() {
        var test = $(this).val();
        var money = fmoney(test);
        console.log(money);
        $(this).val(money);
    });

    function fmoney(val) {
        n = 2;
        s = val;
        s = parseFloat((s + "").replace(/[^\d\.-]/g, "")).toFixed(n) + "";
        var l = s.split(".")[0].split("").reverse(),
            r = s.split(".")[1];
        t = "";
        for (i = 0; i < l.length; i++) {
            t += l[i] + ((i + 1) % 3 == 0 && (i + 1) != l.length ? "," : "");
        }
        return t.split('').reverse().join('') + "." + r;
    }
    </script>