How to change length of Excerpt in WordPress

As a WordPress developer, i needed to change the length of the excerpt.
You can add following function in your themes’s functions.php file.

if(!function_exist('new_excerpt_length') {
    function new_excerpt_length($length) { 
       return 100;
    }
}
add_filter('excerpt_length', 'new_excerpt_length');

Above function will change the excerpt length to 100. (You can change that value as per your need).