<html> <head> <title>Date Example</title> <script type="text/javascript"> function isValidDate(sText) { var reDate = /(?:0[1-9]|[12][0-9]|3[01])\/(?:0[1-9]|1[0-2])\/(?:19|20\d{2})/; return reDate.test(sText); } function validate() { var oInput1 = document.getElementById("txt1"); if (isValidDate(oInput1.value)) { alert("Valid"); } else { alert("Invalid!"); } } </script> </head> <body> <P>Date: <input type="text" id="txt1" /><br /> example: 05/05/2005<br /> <input type="button" value="Validate" onclick="validate()" /></p> </body> </html>