This little jQuery snippet will let you quickly add a limit counter to input fields to display available remaining characters. A nice feature to include for improved user experience.

(function($) {
    $.fn.extend( {
        limiter: function(limit, elem) {
            $(this).on("keyup focus", function() {
                setCount(this, elem);
            });
            function setCount(src, elem) {
                var chars = src.value.length;
                if (chars > limit) {
                    src.value = src.value.substr(0, limit);
                    chars = limit;
                }
                elem.html( limit - chars );
            }
            setCount($(this)[0], elem);
        }
    });
})(jQuery);

To setup the limiter, simply include a call similar to the one below:

var elem = $("#chars");
$("#text").limiter(100, elem);

The first parameter is the character limit integer and the second is a jQuery element representing the target object to display the characters remaining. This is not a replacement for the maxlength parameter or server-side validation, just a visual way to represent the limit.

Click here for the demo.

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