Use the Boolean() method in JavaScript to convert to Boolean. You can try to run the following code to learn how to convert NaN to Boolean in JavaScript.
Example
<!DOCTYPE html>
<html>
<body>
<p>Convert NaN to Boolean</p>
<script>
var myNaN = NaN;
document.write("Boolean : " + Boolean(myNaN));
</script>
</body>
</html>