ECMAScript how to Get Full or Relative Url of web using EcmaScript

Sometimes from client side, you need to know the current web url. And for this little information you don’t want to call EcmaScript’s load function to get information from server side. Actually the information can be found without any server call. You can access the information from ClientContext as shown below.

var context = new SP.ClientContext();
var relativeWebUrl = context.get_url();

Remember the get_url method will only return relative url of the site. As shown in the following table:

Site Collection Url	Site Url	context.get_url() response
http://mysite.com	http://mysite.com	/
http://mysite.com	http://mysite.com/site1	/site1
http://mysite.com/sites	http://mysite.com/sites/site1	/sites/site

So if you need to know the full url of the site you can do so easily with the following script:

function getFullWebUrl() {
    var context = new SP.ClientContext();
    var relativeWebUrl = context.get_url();
    var fullWebUrl = window.location.protocol + '//' + window.location.host + relativeWebUrl ;
    alert(fullWebUrl);
}