<!DOCTYPE html>
<html>
<body>
Password: <input type="password" id="myPsw">
<p>Click the button to change the width of the password field.</p>
<button onclick="myFunction()">Try it</button>
<script>
function myFunction() {
document.getElementById("myPsw").size = "50";
}
</script>
</body>
</html>