<html>
<head>
<meta name="viewport" content="width=device-width, initial-scale=1">
<script type="text/javascript">
window.onload=function(){
//from www.java2s.com
var today = new Date().toISOString().split('T')[0];
document.getElementsByName("setTodaysDate")[0].setAttribute('min', today);
}
</script>
</head>
<body>
<input name="setTodaysDate" type="date">
</body>
</html>