Google Tag Manager

A very recent addition to Google Tag Manager is the Format Value option in all of GTM’s variables. With Format Value, you can modify the output of the variable with a number of pre-defined transformations. This is extremely handy, because you no longer need to create Custom JavaScript variables whose sole purpose of existence it to change the output of other variables to lowercase, or to change undefined values to fallback strings (e. Read More…

**Last updated 18 September 2020: Due to how most browsers now have third-party cookie protections in place, this solution will be very ineffective going forwards. You should instead take a look at a cookieless solution. Some years ago, I wrote a post on how to track cross-domain iframes when using Google Tag Manager and Google Analytics. That solution relied on hitCallback to decorate the iframe, and now that I look back on it, it has its shortcomings. Read More…

In Google Analytics, the concept of a session is the key aggregation unit of all the data you work with. It’s so central to all the key metrics you use (Conversion Rate, Bounce Rate, Session Duration, Landing Page), and yet there’s an underlying complexity that I’m pretty certain is unrecognized by many of GA’s users. And yet, since this idea of a session is so focal to GA (to the point of being overbearing), it’s annoying that the browser isn’t privy to any of the sessionization parameters that Google Analytics applies to the hits sent from the browser to its servers. Read More…

One of the coolest features of Google Analytics and, as a consequence, Google Tag Manager is customTask. It’s a method you can use to add and execute code as the hit to Google Analytics is being generated. I’ve written A LOT about customTask, and much of the feedback I’ve received has been around the question of how to combine all these different tricks into one customTask script. The problem is, you see, that a tag or hit can only have one customTask script attached to it, so the code within must combine all the different tricks I’ve been writing about over the past months. Read More…

Getting cross-domain tracking right in Google Analytics is difficult. Even if you use Google Tag Manager. There are many known issues when cross-domain tracking iframes, for example. Google Tag Manager implements the cross-domain tracking plugin quite handily via the Universal Analytics tag template, and often the easiest way to track links and form submits is to use the Auto-Link Domains option, as described in this great series of posts on cross-domain tracking by Bounteous. Read More…

One of the more difficult concepts in Google Tag Manager is the data model. In essence, the data model is what Google Tag Manager uses to populate the Data Layer variable. You might be tempted to think that it’s the same thing as the dataLayer array, but it’s not. The data model is a representation of the keys and values you push into dataLayer. Whenever you push any key into dataLayer, GTM grabs this key and updates the corresponding key in its data model with the new value, or in the case of objects and arrays merges the old and the new value together. Read More…

It’s time for a very simple #GTMTips article (I know, I always write that these are simple tips, but then they escalate into complex behemoths). Today, we’ll cover a nifty trick you can use with the Element Visibility trigger in Google Tag Manager. This tip was inspired by a question from Eugen Potlog in the Google Tag Manager Facebook group. The use case is that you have an Element Visibility trigger firing for a number of elements all sharing the same CSS selector. Read More…

Tag sequencing was introdced to Google Tag Manager in late 2015. Its main purpose was to facilitate the sequential firing of tags that have dependencies with each other. Due to the asynchronous nature of third-party libraries like Google Tag Manager, it’s difficult to establish an order of completion with tags that compete for their chance to fire. Tag sequencing changed this, as it allows you to establish setup and cleanup tags - the former firing before the main tag, and the latter after. Read More…

One of the great ways to leverage Google Tag Manager in your web analytics tracking is to make use of all the possible custom events that the browser has to offer. One such event is beforeunload. It’s dispatched in the browser when the user is about to unload the page. This means, typically, that the user is about to leave the page after clicking a link, or they are about to exit the browser by either closing the tab or the entire window. Read More…

A Content Security Policy (CSP) is something you’ll configure your web server with to add an additional layer of protection, especially from harmful scripts loaded from third-party vendors. Once you have a CSP in place, all resources loaded and executed by the web page need to pass the CSP directives. For Google Tag Manager, this is very relevant. If you have a CSP in place, you will need to modify it so that Google Tag Manager functions properly. Read More…