What is the Gclid?

Google Click ID (also known as GCLID) is a parameter assigned to the Google Ad and is passed in the URL to track clicks and conversions. The GCLID is only used in Google Ads and is enabled by turning on auto-tagging in the settings. It is used to tie your Google Ads with your Google Analytics account so that the clicks and the conversions can be tracked.

If you enabled auto-tagging, Google automatically assigns a unique Gclid tracking parameter to your Google Ad destination URL. It is also used with offline conversion tracking where you can import third-party data such as the CRM conversion data into your Google Ads account.

Tracking, Tracking and Tracking

As a merchant, you spent a great deal of amount on paid advertisements and it is important to know whether the money was well spent. The ROI is the key metric used to determine if you've earned more than what you've put in. Without collecting analytics data, you wouldn't know how your money was spent, and whether to continue spending on Ads. This is where Gclid comes into play.

You can use Gclid to track clicks, leads, and online & offline conversions. Google automatically tags this parameter for you, so it's automatic and there is no chance of making a mistake such as a misspelling. You can verify the tagging in Chrome -> Settings -> More Tools -> Developer Tools, and by clicking on the "Network" tab. Or, simply look at the final URL and see if ?gclid=XXXXX is appended to your Google Ads.

Some conversions propagating from a lead to an opportunity, to a quotation, and finally, order. Your sales rep may be creating an opportunity, quotation, or order in your order management system, and you may want to import the tracking data into Google Ads. This is called offline conversion tracking, and you can achieve this with the Gclid.

Why Gclid?

There are other tracking parameters like UTM parameters, which you can use across multiple platforms. There are 5 UTM parameters: utm_source, utm_medium, utm_campaign, utm_term and utm_content. UTM parameters will allow you to keep track of various Ad campaigns through the use of 5 parameters, and you can add them to any advertisement including Google, Bing, Facebook, and many others. The tricky part of using UTM parameters is that you have to add 5 different UTM parameters manually to each advertisement you create. Luckily, Google will add UTM parameters automatically on your behalf if you have enabled it in your settings as it's the parameter introduced by Google. If you have to manually add 5 parameters, you'll have to ensure there are no spelling mistakes as incorrect spelling will fail the collection of analytics data.

Gclid on the other hand is only 1 parameter, and it's automatically added by Google. On top of that, Gclid allows you to collect not only 5 UTM parameters but also collect additional information such as:

• Source
• Medium
• Campaign
• Keywords
• Match Type
• Ad Creative
• Ad Group
• Traffic Data
• User Details
• Conversion Tracking

By just adding the Gclid to your Ad campaign, you will be able to collect all 5 UTM data and much more. Gclid is stored in the user's cookie and passed onto Google Analytics for tracking purposes. The traditional "utmz" cookie used to be stored in the user's cookie is no longer available in Universal Analytics, so Gclid can be used instead. Gclid is only used with Google Ads and Google Analytics, so if you're using something else for your Analytics it's not going to do much good. In such a scenario, UTM parameters must be used. There is a UTMZ Cookie Replicator Recipe for Google Tag Manager that you can download and install into your Google Tag Manager that will allow you to store "__utmz" like a cookie (recipe called it "__utmzz" cookie) available in Classic Analytics.

Here is the Google tracking data stored in the user's cookie displayed in JSON format.