In an increasingly cookie-less world, advertisers and platforms are using ever more inventive methods to achieve accurate reporting and measurement. Whilst GCLIDs have been around for a while, they’re pivotal to many new engine features and invaluable to advertisers in a post-GDPR world. 

Where can I get a GCLID from?

A GCLID – or Google Click ID – is used by a number of engine functions, either to link data together or attribute traffic and actions to certain campaigns or keywords. A GCLID isn’t something that can be applied for or collected; it appears within your URL as a parameter. URL parameters are additional pieces of information that are collected and passed within an extended URL, here’s an example. These pieces of information can include a search query, a user’s account ID, and the campaign or keyword they originated from. This information is then used to display data in interfaces or reports (E.g. reflecting how many conversions a specific keyword has achieved). These tracking parameters can be enabled by switching on ‘Auto Tagging’ within your Account Settings menu. 

How does a GCLID work?

A GCLID is a very short piece of code; a unique GCLID is created every time your Google advert is clicked and contains information about the nature of the user and the subsequent landing page visit. Within the Google ecosystem, the GCLID tracks the traffic source (including source, campaign, keyword, search query etc) as well as the time of day and the keyword positioning within the auction. (You may recognize some of these parameters as those that you would set up during UTM tracking; the auto-tagging method mentioned above is essentially automatic UTM tagging within the Google platforms). 

How is the GCLID then used?

Based on the details we’ve mentioned the GCLID collects, it may be unsurprising to learn that a GCLID links Google Ads data with Analytics data, displaying an impression and click within Google Ads, whilst displaying the relevant visit data in Analytics, such as listing the source/medium as Google/CPC and matching on-site performance data with the click itself.

The Enhanced Conversions feature also relies on the GCLID as the common denominator between Google and CRM data to match actions to the same user. The same method applies to offline conversion imports, where the GCLID acts as the thread between different events. 

As you’re tackling measurement challenges in a post-GDPR and cookieless world, remember that the GCLID and its associated features could be just the solution.