Change the value of the datetime attribute:
document.getElementById("myIns").dateTime = "2014-10-13T21:34:07Z";
Click the button to change the value of the datetime attribute of the inserted text.
<!DOCTYPE html> <html> <body> <p>This is a text. <ins id="myIns" datetime="2012-09-15T22:55:03Z">This is an inserted text.</ins> </p>/*from w w w . jav a2 s . com*/ <p id="demo"></p> <button onclick="myFunction()">Test</button> <script> function myFunction() { document.getElementById("myIns").dateTime = "2014-10-13T21:34:07Z"; document.getElementById("demo").innerHTML = "The value of the datetime attribute was changed."; } </script> </body> </html>