Online HTML Editor

<!DOCTYPE html> <html> <head> <title>Input Datetime Value</title> </head> <body> <form> <div> Date &amp; Time: <input type="datetime" id="datetimeSelect" value="2015-08-22T16:24Z"> </div> </form> <button onclick="changeValue()">Change Value</button> <div id="divDisplay"></div> <script> var divDisplay = document.getElementById("divDisplay"); var inputDatetime = document.getElementById("datetimeSelect"); divDisplay.textContent = 'Current value: '+ inputDatetime.value; function changeValue(){ var currDatetime = inputDatetime.value; inputDatetime.value = '2017-03-17T16:24Z'; divDisplay.textContent = 'Updated value from: '+currDatetime+' to: '+ inputDatetime.value; } </script> </body> </html>