The toLowerCase() function of string object converting all character into lower case. Use it for example to convert all character into lowercase.
Syntax
str.toLowerCase()
<DOCTYPE html>
<html>
<head>
<script type="text/javascript">
var str1 = "WWW.TECHSTRIKERS.COM";
document.write(str1.toLowerCase() + "</br>");
</script>
</head>
<body>
</body>
</html>