Add a Character Counter to Excerpt box

excerpt-character-count.php

<?php 
/**
 * Add a Character Counter to Excerpt box
 * URL: http://wpsites.org/?p=10503
 */
 
function excerpt_count_js(){
      echo '<script>jQuery(document).ready(function(){
jQuery("#postexcerpt .handlediv").after("<div style=\"position:absolute;top:5px;right:80px;color:#666;\"><small>Excerpt length: </small><input type=\"text\" value=\"0\" maxlength=\"3\" size=\"3\" id=\"excerpt_counter\" readonly=\"\" style=\"background:#fff;\"> <small>character(s). (128 Characters MAX)</small></div>");
     jQuery("#excerpt_counter").val(jQuery("#excerpt").val().length);
     jQuery("#excerpt").keyup( function() {
     jQuery("#excerpt_counter").val(jQuery("#excerpt").val().length);
     if ( jQuery("#excerpt_counter").val() >= 101 ) {
        jQuery("#excerpt_counter").css("color","red");
     } else {
        jQuery("#excerpt_counter").css("color","green");
     }
   });
});</script>';
}
add_action( 'admin_head-post.php', 'excerpt_count_js');
add_action( 'admin_head-post-new.php', 'excerpt_count_js');
;?>