$("input[type=checkbox]").click(function(){ var $count = $("input[type=checkbox]:checked").length; var $not = $('input[type=checkbox]').not(':checked') if($count >= 3) { $not.attr("disabled",true); }else{ $not.attr("disabled",false); } });
<input type="checkbox" value="1"><br /> <input type="checkbox" value="1"><br /> <input type="checkbox" value="1"><br /> <input type="checkbox" value="1"><br /> <input type="checkbox" value="1"><br /> <input type="checkbox" value="1"><br /> <input type="checkbox" value="1"><br /> <input type="checkbox" value="1"><br /> <input type="checkbox" value="1"><br /> <input type="checkbox" value="1"><br /> <input type="checkbox" value="1"><br /> <input type="checkbox" value="1"><br /> <input type="checkbox" value="1"><br /> <input type="checkbox" value="1">