You might be wondering how analytics tools are capable of monitoring website performance. Analytics tools like Google Analytics can only monitor websites that have been tagged for monitoring. In other words, a tag, or piece of code, must be run on each website to make these tools aware of them. This reading describes two methods of tagging: using a global site tag or using Google Tag Manager.
Global site tagging
Google’s global site tag, gtag.js, is a single tag that can be implemented on a website. It is added to the HTML <head> element of each website’s page. The <head> element contains the metadata for a page—information that isn’t displayed but is important for website management. This global tag supports multiple Google products in addition to Google Analytics. After adding this tag, other products like Google Ads can also be turned on for the site so metrics for the traffic coming from Google Ads can be collected.
The main advantage of using global site tagging is that it is designed for use with all Google products and services. Additional tags are required to monitor traffic from other advertising or media platforms, or to enable monitoring with other analytics tools. Use Google Tag Manager to work with additional tags for non-Google platforms.
Google Tag Manager
For more universal tagging, Google’s solution is Google Tag Manager, a tag management system (TMS) that enables the deployment and management of many tags for multiple advertising platforms and systems in a simple and centralized way. After a small snippet of Tag Manager code has been added to a website, analytics and measurement tags can be deployed to many platforms from Tag Manager’s web-based interface.
Google Analytics 4 tags in Google Tag Manager
Google Tag Manager supports Google Analytics 4 properties with two tags:
- Google Analytics: GA4 Configuration
- Google Analytics: GA4 Event
The Google Analytics Configuration tag initializes Google Analytics data collection for a Google Analytics 4 property and has to be added to all pages. This enables basic Google Analytics 4 measurements, which include automated events and enhanced measurement events, if the enhanced measurement feature is enabled during the setup phase.
The Google Analytics 4 Event tag, which can be added to particular interactions or web pages enables custom events to be sent to Google Analytics 4 property. Custom events enable the monitoring of metrics beyond those automatically sent for every event or those enabled by turning on enhanced measurement.
The primary differences between using Google’s global site tag and Google Tag Manager are:
Resources for more information
You can refer to the following links for more information about using the global site tag or Google Tag Manager:
- Tag Manager and gtag.js: Tag Manager help article describes both tagging methods
- Google Analytics 4 tags: Tag Manager help article describes tags for GA4 properties
- Deploy Universal Analytics with Tag Manager: Tag Manager help article describes how to deploy tags for UA properties