jQuery Mask Plugin - Issue Report
You don't need to start from scratch..
HTML
<script src="http://igorescobar.github.io/jQuery-Mask-Plugin/js/jquery.mask.min.js"></script>
<h4 id="cr1">Até 30 dias<input type="text" placeholder="R$ 0,00" id="cr11" name="ncr11" class="money2" value="12225"/></h4>
JavaScript
$('.money2').mask("#.##0,00", {
reverse: true
});