Data Journal - Advanced Google Tag Manager Setup

Perhaps the most famous term related to Google Tag Manager is the dataLayer.
Whether you’re working on code to track specific behavior or deploying tags in GTM, terms like dataLayer events and dataLayer variables always come up. Not only that, there are Chrome extensions dedicated to investigating the dataLayer and its contents — most notably DataLayer Checker.

But what if we told you that the dataLayer can become something else?
What if you could rename the dataLayer to anything you like — and make anyone trying to peek into your implementation get an error instead?

In this tutorial, we’ll show you how to rename Google Tag Manager’s dataLayer safely and correctly.
A word to the wise: if you aren’t familiar with how the dataLayer works or don’t have version control in your codebase, do not modify your GTM installation unless you can revert it easily.

Quick recap on GTM’s dataLayer

The dataLayer is a window-level array used by both Google Tag Manager and gtag.js to store structured data about user interactions and page context. GTM reads from this array to trigger tags, populate variables, and capture event metadata. It’s the single most important piece of the GTM architecture.

Customizing the dataLayer’s name

To rename the dataLayer, start by locating your Google Tag Manager installation script, the one added to your site’s <head> section. It should look like this:

<!-- Google Tag Manager -->
<script>
(function(w,d,s,l,i){
  w[l]=w[l]||[];
  w[l].push({'gtm.start': new Date().getTime(), event:'gtm.js'});
  var f=d.getElementsByTagName(s)[0],
      j=d.createElement(s),
      dl=l!='dataLayer'?'&l='+l:'';
  j.async=true;
  j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;
  f.parentNode.insertBefore(j,f);
})(window,document,'script','dataLayer','GTM-XXXXXXXX');
</script>
<!-- End Google Tag Manager -->

In this script, the last line tells the function to run in the context of the current window and document, create a <script> element, use dataLayer as the global queue, and load the GTM container with ID GTM-XXXXXXXX. Now that we understand it, renaming the dataLayer is as simple as changing that one argument. For example, we can rename it to analyticsQueue:

<!-- Google Tag Manager -->
<script>
(function(w,d,s,l,i){
  w[l]=w[l]||[];
  w[l].push({'gtm.start': new Date().getTime(), event:'gtm.js'});
  var f=d.getElementsByTagName(s)[0],
      j=d.createElement(s),
      dl=l!='dataLayer'?'&l='+l:'';
  j.async=true;
  j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;
  f.parentNode.insertBefore(j,f);
})(window,document,'script','analyticsQueue','GTM-XXXXXXXX');
</script>
<!-- End Google Tag Manager -->

How GTM recognizes your renamed dataLayer

Google Tag Manager doesn’t have any interface or “container setting” to rename the dataLayer. The renaming is handled entirely by the script above. When you change 'dataLayer' to 'analyticsQueue', the code automatically adds &l=analyticsQueue to the GTM script URL https://www.googletagmanager.com/gtm.js?id=GTM-XXXXXXXX&l=analyticsQueue. This URL parameter tells GTM which global array to read from. As long as this script executes before any GTM events fire, GTM will use window.analyticsQueue as its event queue instead of window.dataLayer.

Confirming the rename

There are two easy ways to confirm that your rename worked.

1. Console test

Open your browser’s developer tools and type:

window.dataLayer

You should see undefined, which means the original dataLayer no longer exists. Now type:

window.analyticsQueue

You’ll see something like this:

[
  {
    "gtm.start": 1759538813330,
    "event": "gtm.js",
    "gtm.uniqueEventId": 3
  },
  {
    "event": "gtm.dom",
    "gtm.uniqueEventId": 4
  },
  {
    "event": "gtm.load",
    "gtm.uniqueEventId": 10
  }
]

That’s your GTM queue, exactly what you’d normally see inside dataLayer.

2. Checking the `google_tag_manager` object

In the console, type:

window.google_tag_manager

Then expand your GTM ID key (for example, GTM-T953W4BZ). Inside, look for the dataLayer property. Before renaming, it should look like:

{
  "GTM-T953W4BZ": {
    "dataLayer": { "name": "dataLayer" }
  }
}

After renaming, you’ll see:

{
  "GTM-T953W4BZ": {
    "dataLayer": { "name": "analyticsQueue" }
  }
}

Important considerations

Once renamed, window.dataLayer.push() will no longer work. Any code referencing dataLayer must now use your new name, for example:

window.analyticsQueue.push({
  event: 'purchase',
  value: 129.99
});

This is the only way GTM will recognize your events, since you’ve redefined its listening array.

Final thoughts

By customizing your dataLayer name, you’ve set up a more advanced and personalized GTM configuration, one that adds a small layer of obfuscation and control over how your analytics data flows. Just remember to always test your setup thoroughly in Preview mode before deploying to production.