This is the first in a series of blog posts around Google Tag Manager. At iProspect, we have been using multiple vendors for container tags since 2010. This series focuses specifically on Google’s new Tag Manager, providing an overview of the tool, helpful tips, hints, and learnings we have found.

What is a Container Tag?

A container tag is a code snippet used in web development that removes the need for multiple data tracking codes being placed directly on the site. Instead, one code is placed on every page on a site. This code literally acts as a container whereby all tracking codes can be placed off site in the Google Tag Manager interface and fired from the one code on the site. This means that you can update, add or remove your tracking codes, through the Google Tag Manager interface, avoiding website development times.

How does it work?

When a site loads or a specific action is completed on the site, the tag will be activated. It will search the Google Tag Manager database located in the cloud. It will then fire any tracking codes that are held in the account and that match a set of specific rules that you have defined.

google tag manager

Figure 1A Container Tag: Google Tag Manager fires, checks the cloud, pulls the tags that fit the criteria and fires them. 

Why are container tags needed?

Different types of media use different tools to track volume and conversions. For example, the onsite tracking may be a tool like Google Analytics, or Webtrends. The site may also have a display banner campaign to help to drive traffic. This may be measured by tools like DFA (DoubleClick for Advertisers) or MediaMind. If a PPC campaign is running, it may be measured through a separate tool like Adwords. Each of these types of tools has their own JavaScript codes that are placed on a site.

Without a container tag all of these different types of codes need to be placed on pages of a site in different places of the source code. Onsite tracking is there all the time, but other tools may need their tracking to be placed on a site for a length of time whilst a campaign is running.

A container tag is needed to make this process far more manageable, and at times, more cost effective. There is no need to go through development or need to redeploy the site when a change is needed to the tracking code; this is because the container tag can be updated through the Google Tag Manager interface.

What types of tracking codes can be fired through Google Tag Manager?

Google Tag Manager TypesAt the time of writing, Google Tag Manager has integrations with Adwords, DoubleClick, Google Analytics (classic and universal), MediaPlex, Adroll, Turn, AdAdvisor, Bizo, Media6Degrees, and comScore. It also allows you to input in custom HTML tags and custom Image Tags.  The custom HTML tag can include HTML, JavaScript, JQuery, and can be used to fire non-Google vendors, like Webtrends (as long as the Webtrends version is the asynchronous).

Tracking codes can be at a page or event level. For example, a Google Analytics code can fire on every page, a Floodlight can fire on certain pages, or a Google Analytics event can fire on a PDF download button.

How can the tags be viewed and modified?

All tracking codes are placed in the Google Tag Manager interface. Most are placed using the pre-defined choices that Google Tag Manager have set up (e.g. Google Analytics standard codes, DoubleClick Floodlight Counters). For any tracking codes that do not have a pre-defined choice, or if a more advanced setup is needed, then a custom HTML tag or custom Image tag can be used. The tracking code is created and then a ‘rule’ is set up so that the tracking code fires on a certain page or when a certain element within the page is interacted with (e.g. on a button click).

The next blog post will run through the interface in more detail; however below is an example of how the codes are displayed when placed in the interface. Any of these tags can be modified or removed through the interface at any time and new tags can be added.

Google tag manager tags

Advantages of using Google Tag Manager:

  • No need to redevelop and redeploy sites when there is a new media campaign
  • No need to hardcode on events with long lead time – elements on site can be tracked without the need for additional code (through advanced coding techniques)
  • Improves site performance
  • Multiple tools can fire on one action – e.g. an Adwords conversion tag and DoubleClick can fire on one button or page.
  • Floodlights and Adwords can easily fire onClick rather than on the load of a page

In the next Google Tag Manager Blog post, we will be running through an overview of Google Tag Manager itself, breaking down the parts to it and what to do to set up a simple tag. Subscribe below to be alerted to new iProspect blog posts.

Rachel Sweeney

Rachel Sweeney


Rachel Sweeney is Digital Specialist, Web Analytics & Conversion Optimisation at iProspect.