To check whether a value is a number in JavaScript, use the isInteger() method. This method checks whether the value is a number or not.
Example
You can try to run the following code to check the value is a number or not −
<html> <head> <title>JavaScript isInteger() Method </title> </head> <body> <script> document.write(Number.isInteger(30)); document.write("<br>"+Number.isInteger(true)); document.write("<br>"+Number.isInteger(false)); document.write("<br>"+Number.isInteger(-30)); </script> </body> </html>