<!DOCTYPE html>
<html>
<body>
Name: <input type="text" id="myText">
<p>Click the button to set the maximum number of characters allowed in the text field.</p>
<button onclick="myFunction()">Try it</button>
<p id="demo"></p>
<script>
function myFunction() {
document.getElementById("myText").maxLength = "4";
document.getElementById("demo").innerHTML = "Maximum number of characters allowed in the text field is now 4.";
}
</script>
</body>
</html>