What is Google Tag Manager and what makes it useful?

September 29, 2017

Do you use code to track and analyse the users on your site/app? Then you may have heard of Google Tag Manager, which has become a hit in web analytics and digital marketing. But what is Google Tag Manager really, and what makes it useful?

What is Google Tag Manager?

Google Tag Manager is what is known as a Tag Management System, which manages tags made up of JavaScript snippets. These tags send information to third parties from your webpage or app.

That’s the short version.

To flesh the idea out a bit: instead of changing the page’s source code, Google Tag Manager (or GTM) lets you use its interface to create, modify and check what is tracked and how.

All you need to do is add a short script, known as a container tag, to the webpage or app, and then you can control everything from GTM.

Being able to create, modify and control the options for analysing your page/app all in one place is also one of GTM’s major benefits, as discussed in detail below.

In other words, GTM should not be confused with Google Analytics (more on this below); it’s a totally different tool. Still, it’s perfectly possible to use Google Tag Manager in order to use Google Analytics; several other programs can also be controlled via the GTM interface, such as Hotjar, Adwords and more.

Implementing Google Tag Manager is fast and easy; read more here.

What did people do before Tag Management systems?

Before GTM, JavaScript in webpages or mobile apps needed to be hard-coded in the source code. As a web analytics manager, you had to go through the developers if you wanted to implement even the tiniest change in terms of how you track/analyse.

If you wanted to track events, such as clicks on your page, you had to add this as an item on a developer’s to-do list. At which point the analytics tasks had to compete with other, “more important” issues, bugs, etc.

From the developers’ perspective, this also involved a great deal of fiddling with JavaScript/jQuery/Other to get the tracking to work. Not exactly the most enjoyable use of a developer’s time.

Like we said above, with GTM this is a thing of the past (almost).

You may think you’re already sold on implementing Google Tag Manager, but hold your horses! There’s more!

What are the benefits?

So that you can convince yourself and others that it’s a good idea to use Google Tag Manager to help your project/business, we have listed a few benefits below.


We’ll start by getting this obvious benefit out of the way: It’s free.

Google Tag Manager provides many robust functionalities free of charge. For large organisations, there may be a need to upgrade to Google Tag Manager 360, which does carry a cost; but for small to medium-sized businesses, we recommend using the free version of GTM.

(Continuing to use Google’s services to handle data and whether this constitutes a cost in itself is a discussion for another time)

Speeds up implementation

Like we said, Google Tag Manager lets you manage all types of tracking code from an interface separate from the one where you handle the source code. This means that you do not have to go through developers to change what you want to be able to track.

In many cases this helps you save a great deal of time, sometimes as much as several hundred percent, when implementing tags/tracking code.

If you work using agile methods, such as Scrum, there may be a risk that the implementation of tracking code will be accorded low priority compared to other tasks and stories. With Google Tag Manager, your analytics manager – regardless of whether he or she is code-savvy – can quickly implement tracking code changes without necessarily having to consult/interact with developers.

Birds of a feather flock together (GTM + Google Analytics)

Google likes Google, meaning that Google Tag Manager also likes Google Analytics.

To clarify, Google Tag Manager is no substitute for Google Analytics, but is a way of adding Google Analytics tracking to your webpage/app.

You can use Google Analytics without Google Tag Manager and vice-versa. Lika barn leka bra (Swedish for ‘birds of a feather flock together’), Markus Krunegård sang, and even though he probably didn’t have Google Tag Manager and Google Analytics in mind, it’s true of these services too. Google likes Google, meaning that the two tools work well together.

Because many businesses use Google Analytics to analyse their webpages and apps, this often seamless integration should be seen as a clear benefit that can be gained by using GTM as your Tag Management System.

Can be used by non-coders

You needn’t be a coder to use Google Tag Manager.

Thanks to Google Tag Manager being free, open to everyone and well-documented, it is relatively easy to get up to speed and learn how to use it. It’s stuffed to the gills with tutorials, blog posts (meta) and materials from both Google and third parties to help you get started.

It’s 99% true that you don’t need to be a coder to use GTM. Generally speaking, you can implement most of what you need using predefined tags provided by Google Tag Manager. The interface is very user-friendly, and you will usually not have to write a single line of code to start tracking something on your page/app. For a few more complicated types of tags, it’s a good idea to have some baseline familiarity with JavaScript/HTML/CSS when you add custom code, but plenty of documentation and guides are available online in this case as well.

Not having to be a coder to use GTM is often a plus, as not everyone who is involved in web projects or interested in analytics will have coding skills. GTM lets you involve these people more intimately in the development process. They can then pick up some of the slack by handling some of the time-consuming tasks that used to fall to the developers.

Event tracking

Event tracking, i.e. tracking events that the user performs on your page/app, can include clicks, video interactions, AJAX forms, scroll or hover. In the past, event tracking meant that you had to add code to the source code. Google Analytics was able to track sessions and pageviews, while events like these required workarounds.

With Google Tag Manager’s auto-event tracking, you no longer need to add code manually. Instead, you can create events around links or buttons on your site/app, directly from the tool and following a clear structure.

It’s often of considerable interest to see how users interact with the content in your service; it goes without saying that the ease of event tracking in GTM should be considered a clear advantage.

Collect all third-party pixels in one place

If you spend advertising money on Facebook, AdWords or any other advertising platform, you have probably already hard-coded a ton of marketing, retargeting and conversion pixels on your page/app. These pixels are important in terms of being able to measure the degree to which your marketing efforts are paying off on your page/app, and are thus commonly used. It’s easy for things to get quite messy with all these pixels and code scattered all over your page.

You may be the type of person who already has all of these pixels neatly documented in some way, but that just means that you’ll like GTM even more.

That’s because with GTM you’ll have all these pixels gathered in one place. Some of the pixels are even built in! It’s easy to get an overview of what is going on on your page/app in terms of pixels and marketing. Once a campaign is over, you can easily disable or remove the campaign-specific pixel. You can also add new pixels from the same place. Pretty, pretty nice.

Debug mode and Version control

Another snazzy feature offered by Google Tag Manager is that it includes built-in debug capabilities that let you and your team test and debug every update prior to publication. This way you can make sure that the tags work before they go live.

When you then publish updates, a new version of Google Tag Manager will be created. One advantage of this approach is that you can easily revert to a previous version at any time, if desired. This makes it easy to get an overview of how you work and the way you keep your tags organised. It also simplifies troubleshooting, as you can quickly and easily revert to a functioning version and compare.

Disadvantages + other options

Like most things in life, there are also disadvantages to using Google Tag Manager.

Keep an eye on GDPR

Google Tag Manager can definitely be used to collect data about users, and thus naturally about people as well. At a time when Google’s future as regards GDPR and data management is still up in the air, it’s hard to prophesy whether GDPR will affect the use of GTM. But you should keep your ears and eyes open about how GDPR will affect both Google and your website or company in general.

Make sure you get your user rights right

Because the tags, as well as the UX and design, can be controlled directly from the GPM interface, who has access to the interface needs to be tightly controlled.

It can be a recipe for trouble if the wrong person gains access. It’s not always easy to know at first glance who has permission to do what in Google’s tools. Make sure you keep an eye on this!

Other alternative tag management systems

There are of course alternatives to Google Tag Manager. Even though the point of this post was to highlight GTM in particular, it can’t hurt to mention a few alternative solutions. There are loads of tag management systems out there – here are a few that you can check out.

  • Adobe DTM – used by many large companies with complex requirements and architectures.
  • Tealium – Just like Adobe DTM, mostly used by large organisations that manage more than one site with heavy traffic and complex requirements.
  • Signal – focuses on marketing tags in particular.
  • Ensighten – Aimed at security-focused and process-driven development projects.

Now you’ve learned about some of the benefits (along with the few drawbacks) of Google Tag Manager. We hope this information will help you in both your development and marketing efforts going forward.

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