How to remove _ga query string from URL - google-analytics

Question

I have a multidomain website for which there is GA tracking. Recently we moved to Universal Analytics and noticed that whenever the domain is changed (from US to Korean/Japanese), a _ga=[random number] is appended to the URL
i.e. from
abc.com
when i click on the japanese site, the URL becomes
japanese.abc.com/?_ga=1.3892897.20937502.9237834
Why does this happen?
How can I remove the _ga part of the URL?
Appreciate your help.

Answer 1

This is needed for cross-domain-tracking (i.e. track people who cross domain boundaries as one visitor and not as one visitor per domain). If you want cross domain tracking you cannot remove this. The _ga - part is the client id which identifies a session and since it cannot be shared via cookies (which are domain specific) it has to be passed via the url when the domain changes.
Since somebody set your site up for cross domain tracking I guess you actually want this (it does not happen by default). The parameter is a necessary side effect of cross domain tracking with Universal Analytics. If you do want this look in the tracking code for any of the linker functions mentioned in the documentation and remove them.
Updated to answer the questions from the comment.
Is there no way to remove the _ga string and still have the cross
domain facility?
No, currently not. Browser vendors work on better ways of cross
domain communication so there might be something in the future, but
at the moment the parameter is the best way.
Also, what if some user randomly changes the _ga value and presses
enter? How will GA record that?
If the user happens to create a client id that has been used before
(highly unlikely) his visit would be attributed to another user.
Realistically Google Analytics will just record him as a new user.
Updated
For those who like to play I did a proof of concept for cross domain tracking without the _ga parameter. Something along those lines could be developed further, as-is it is not suitable for production use.
Update: David Vallejo has a Javascript solution where the _ga parameter is removed via the history API (so while it is still added it is for all intents and purposes invisible to the end user). This is a more elaborate version of Michael Hampton's answer below.

Answer 2

I'm using HTML5 history.replaceState() to hide the GA query string in the browser's address bar.
This requires me to construct a new URL having the _ga= value removed (you can do this in your favorite language) and then simply calling it.
This only alters the URL in the address bar (and in the browser's history). Google Analytics still gets the information passed in via the query string, so your tracking still works.
I do this in a Go html/template:
{{if .URL.RawQuery}}
<script>
window.history.replaceState({}, document.title, '{{.ReplacedURL}}');
</script>
{{end}}

Answer 3

I was asked to remove this tag after it started showing up when we split our website between two domain names. With Apache Rewrite Rules:
RewriteCond %{QUERY_STRING} _ga
RewriteRule ^(.*)$ $1? [R=301,NC,L]
This will remove the tag, but will not be able to pass the _ga params to Google Analytics.
If the user doesn't mind a short refresh, then adding this code to every page
<?php
list($url, $qs) = preg_split('/\?/',$_SERVER['REQUEST_URI']);
if (preg_match('/_ga=/', $qs) ) header( "refresh:1;url=${url}" );
?>
will refresh after a second, removing the query string, but allowing the Google Analytics action to take place. This means that by the time your user has bookmarked or copied your URL, the pesky _ga stuff has long gone.
The above code will throw away ANY query string. This version will just strip out the '_ga' argument.
$urlA = parse_url($_SERVER['REQUEST_URI']);
$qs = $urlA['query'];
if (preg_match('/_ga=/',$qs)) {
$url = $urlA['path'];
$newargs = array();
$QSA = preg_split('/\&/',$qs);
foreach ($QSA as $e) {
list($arg,$val) = preg_split('/\=/',$e);
if ($arg == '_ga') continue; # get rid of this one
$newargs[$arg] = $val;
}
$nqs = http_build_query($newargs);
header( "refresh:1;url=${url}?${nqs}" );
}

Answer 4

You can't stop Google from adding the tag, but you can tell Analytics to ignore it in your reports. Thanks to Russ Henneberry for this: http://blog.crazyegg.com/2013/03/29/remove-url-parameters-from-google-analytics-reports/
It was written before Universal was released, so the language is outdated - now you create a new "view" (rather than "profile"). Creating a new view ensures that you still have the raw data in your default view (just in case you ever need it), so it's really the best solution (keeping in mind that you can't ever apply new settings retroactively in G Ax). Good luck!

Answer 5

You can't remove the _ga parameter from the URL on the website...BUT you can use an Advanced filter in Google Analytics to remove the query parameter from the reports!
Like this:
1) Field A: Request URI
Pattern: ^(.+)\?_ga
2) Field B: not needed
3) Output To -> Constructor
Field: Request URI
Pattern: $A1
This filter that will strip off all query parameters when _ga is the first parameter shown. You can get a lot fancier with the regex, but this approach should work for most websites.

Answer 6

See this page: https://support.google.com/tagmanager/answer/6107124?hl=en
& search for "use hash as delimiter"
Setting this value to true allows you to pass the value through a hash tag instead of through a query parameter
Should fix it

Answer 7

One way to handle this is to use the history.replaceState Javascript function to remove the query string from the URL after the page is finished loading and Google Analytics has done its thing. However, if you remove it too soon, it'll affect GA functionality (one visitor will show as multiple visitors). I've found that the following Javascript (with a 3-second delay)
<script defer src="data:text/javascript,async function main() {await new Promise(r => setTimeout(r, 3000));window.history.replaceState({}, document.title, window.location.pathname);}main();"></script>
I used "window.location.pathname" for convenience so that you can use the same script on many pages. However, you can also do like this (for the top page of the site):
<script defer src="data:text/javascript,async function main() {await new Promise(r => setTimeout(r, 3000));window.history.replaceState({}, document.title, '/');}main();"></script>
Or for a sub-page:
<script defer src="data:text/javascript,async function main() {await new Promise(r => setTimeout(r, 3000));window.history.replaceState({}, document.title, '/something/something.html');}main();"></script>
I did the "data:text/javascript" thing instead of a true in-line script so I could apply "defer" to it, although this probably isn't necessary if you're using a sufficiently long delay value.

Answer 8

You can filter out all (or only include) "?_ga=" parameters in Google Analytics for reporting purposes. I would also highly recommend adding a canonical to the base URL -- or adding the parameters to Google Webmaster Tools -- to avoid duplicate content.