<script type="text/javascript">
function calpercentge(e)
{
var pcnt=6;
var nprice=0;
var spval= e.value;
if(spval == 'NaN' || spval == "") {
spval = 0.00;
document.getElementById("product_price").value = spval.toFixed(2);
} else {
spval = parseFloat(spval);
pcnt = parseFloat(pcnt);
var pcnt_rs = parseFloat( parseFloat( spval*pcnt )/100 );
nprice = parseFloat(spval + pcnt_rs);
document.getElementById("product_price").value = nprice.toFixed(2);
}
}
</script>
<!-- -->
<script>
$(function () {
$("#price").on('keyup change',function(){
calpercentge(this);
});
});
</script>