Use the modulus % operator to determine if a number if odd or even in JavaScript.
Example
You can try to run the following code to check if a number is odd or even −
Live Demo
<!DOCTYPE html> <html> <body> <script> var num = 5; document.write("Number = "+num+"<br>"); if(num % 2 == 0) { document.write('Number is even!'); } else { document.write('Number is odd!'); } </script> </body> </html>
Output
Number = 5 Number is odd!