How to get random element in jquery?

You can write a custom filter (taken from here):

jQuery.jQueryRandom = 0;
jQuery.extend(jQuery.expr[":"], {
    random: function(a, i, m, r) {
        if (i == 0) {
            jQuery.jQueryRandom = Math.floor(Math.random() * r.length);
        };
        return i == jQuery.jQueryRandom;
    }
});

Example usage:

$('.class:random').click()

The same thing but as a plugin instead:

​jQuery.fn.random = function() {
    var randomIndex = Math.floor(Math.random() * this.length);  
    return jQuery(this[randomIndex]);
};

Example usage:

$('.class').random().click()