this is html that checks if the text entered is a palindrome, it excludes anything that is neither a letter nor a number.

palindromeChecker.html

<!DOCTYPE=html>
<p>enter text and press button to check if it is  a palindrome</p>
<input id="palcheck">
</input>
<button id="myBtn" onclick="getStatement()">Button</button>
<h1 id="output"></h1>
<script type="text/javascript">

/**
 * @param {string} s
 * @return {boolean}
 */
function getStatement(){
	txt = (document.getElementById("palcheck").value);
	if (isPalindrome(txt)){
		document.getElementById("output").innerHTML = "the text above is a palindrome pal"
	}
	else{
		document.getElementById("output").innerHTML = "the text above is not a palindrome pal"
	}
}

var isPalindrome = function(s) {

	n = s.split('').filter(char => /[a-zA-Z0-9]/.test(char)).map(a=>a.toLowerCase()) 
	return JSON.stringify( n) === JSON.stringify([...n.reverse()])
};
// test = "A0 man, a plan, a canal: Panam0a"
// console.log(isPalindrome(test))


</script>
</>