 <p>The XDR-object of InternetExplorer currently is not supported by jQuery, you'll need a plugin like <a href="https://gist.github.com/1114981" rel="nofollow"><strong>jquery.xdomain.js</strong></a></p> <p>But there is another issue: the timezone-API requires the HTTPS-protocoll , when the document that requests the API doesn't use HTTPS, it will still fail in IE.</p> <p>But you may use a serverside proxy-script that fetches the result from the timezone-API and delivers it to jQuery</p>