Cross-domain tracking

« Back to Glossary Index

What is cross-domain tracking

Cross-domain tracking enables Google Analyticsto track visitors as consecutive sessions on two or more related websites. For example, when tracking and in the same GA Web property.

How does it work and what does it do?

Google Analytics uses a first-party cookie called _ga. For our example, this means that 1 cookie is used for,, and other subdomains. This is easily done by setting the cookie domain setting in GTM to automatic.

This _ga cookie stores information about the visitor and his session and has the following properties:

Cookie name - by default "_ga".
Cookie domain - this is the domain where the cookie is set. For it means that the cookie domain is ''. (without the "www" prefix)
Cookie path - this is the path where the cookie will be stored. This is the root directory of the "/" domain.

Cookie Expires - This is the time in seconds after which the _ga cookie will expire. By default, the _ga cookie expires after 2 years from the time of the last update.

Since it is a first-party cookie, it cannot share this information with other domains. This is where cross domain tracking comes into play. In this case, we need to instruct it to pass the values of the Cookies from with the cookie from

This sends the cookie value _ga to the URL appended to the domain change, using the query string by default. If you don't like the query string, you can also change it to a URL-fragment. GA recognizes the parameters added in these URLs and ensures that the GA cookie uses these values.

What are subdomains?

Often the Cross-domain tracking with the Subdomain-tracking. One Subdomain is basically a subdivision of a domain that, if used correctly, helps to divide different areas of the website. In short, we can explain it with this structure:

What if we do not do this?

It has a great impact on what people do on your website. The wrong distribution of traffic sources has increased the number of sessions. It's impossible to judge which marketing channels are more successful than others in generating valuable Traffic to generate. The list goes on. In short, there is no way to make decisions based on the data collected in Google Analytics.

Of course, there are also some scenarios where cross-domain tracking cannot be performed, mainly because GA cannot be implemented on those domains. One such scenario applies to payment gateways (for those that have transactional websites). In this case, you need to use the GA exclusion list, which can be accessed from the GA admin panel.

« Back to Glossary Index


What is Cross Domain Tracking? arrow icon in accordion
Cross domain tracking is a process that allows the same user session to be tracked across multiple domains. This allows brands to track the activities of a single user across multiple domains. This allows brands to get a clearer picture of users and better understand their behavior and interactions.
What is Cross Domain Tracking used for? arrow icon in accordion
Cross domain tracking is mainly used to get a better understanding of the behavior of a single user across multiple websites. It can also be used to measure the performance of campaigns that run across multiple domains and to analyze the data associated with specific users.
What is a cross domain cookie? arrow icon in accordion
A cross domain cookie is a special browser cookie used by a website to store and transfer data about a user on multiple domains. These cookies allow brands to track between the different domains on which a user is active.
How does cross domain tracking work? arrow icon in accordion
Cross domain tracking is based on the use of cross domain cookies, which are used on all sites that are to be tracked. These cookies store a unique token associated with the user, and the token is passed between sites when the user switches. This allows brands to uniquely identify when the same user moves from one site to another.
What are the advantages of cross domain tracking? arrow icon in accordion
Cross domain tracking offers brands many benefits, including better insights about customers obtained through better tracking of their behavior and the ability to monitor the performance of campaigns that run across multiple sites. It also provides greater accuracy in monitoring user activity and enables brands to better understand how their customers respond to websites.
Can cross domain tracking affect my customers' privacy? arrow icon in accordion
No, cross domain tracking is a responsible approach that protects user privacy. No personal or sensitive information is transmitted or stored, and all data that is transmitted is anonymized.
What kind of information is collected via cross domain tracking? arrow icon in accordion
Cross domain tracking only collects anonymous and aggregated data that gives brands a better understanding of their customers' behavior. This includes information such as the number of page views, the duration of a session, and the frequency of visits to a website.
Will larger companies use cross domain tracking? arrow icon in accordion
Yes, cross domain tracking is used by many larger companies. Large companies have many websites or domains and need to improve their understanding of the customers who use their products and services. Cross domain tracking allows them to gain insights into customer activity across multiple domains.
What technologies are needed for cross domain tracking? arrow icon in accordion
To use cross domain tracking, brands must first set up a cross domain cookie tracking system on their website. This requires the use of a tag management system and the integration of appropriate cloud solutions.
Can companies perform cross domain tracking themselves? arrow icon in accordion
Since cross domain tracking is a complex task, it is better to use the services of an expert. Experts can set up a tracking system for companies that records and tracks customer behavior across multiple domains.

With top positions to the new sales channel.

Let Google work for you, because visitors become customers.

About the author

Social Media & Links:

Your free gift!
Our SEO strategy

You want more visitors and better Google rankings?

Watch our free SEO strategy webinar now and understand where your SEO levers are and how to tackle them head on.