<html> <head> <script type="text/javascript" src="js/jquery-1.3.2.js"></script> <script type="text/javascript"> $(document).ready(function(){ $("input").keyup(function (e) { if (e.which > 65 ) { alert(e.which); } }); }); </script> </head> <body> <body> <input type="text" /> </body> </html>