<script type="text/javascript">
function cutHex(h) { return (h.charAt(0)=="#") ? h.substring(1,7) : h}
function toR(h) {return parseInt((cutHex(h)).substring(0,2),16)}
function toG(h) {return parseInt((cutHex(h)).substring(2,4),16)}
function toB(h) {return parseInt((cutHex(h)).substring(4,6),16)}
function hex(h) {document.getElementById('rgb').value = 'rgb('+toR(h)+','+toG(h)+','+toB(h)+')'}
</script>
<input type="text" onkeyup="hex(this.value);"> <input type="text" id="rgb">

