The data layer is a structured format for collecting and storing data on your website, which can then be accessed by Google Tag Manager (GTM). It’s necessary for passing custom information from your website to GTM, enabling more precise tag firing and data handling, essential for advanced tracking and analysis.
Initialization:
- Before the Google Tag Manager (GTM) snippet, you should initialize the data layer on your website. This is done by adding the following code in the <head> section of your HTML:
<script>
window.dataLayer = window.dataLayer || [];
</script>
- This code creates a new JavaScript object called dataLayer if it doesn’t already exist.
Populate Data Layer:
- You can populate the data layer with information by using the push method. This can be done anywhere on your page, but it’s often done in the <head> or <body>:
window.dataLayer.push({
‘variable_name’: ‘variable_value’
});
- Replace ‘variable_name’ with the name of your variable, and ‘variable_value’ with the value of your variable. You can push as many variables as you need, and they can be used later in GTM.
Dynamic Data:
- If your website has dynamic elements, such as a shopping cart, you might need a developer to write JavaScript that pushes data to the data layer whenever the content changes.
Event Tracking:
- You can also use the data layer to track events. When an event occurs, you push an event and any associated data to the data layer:
window.dataLayer.push({
‘event’: ‘button_click’,
‘button_label’: ‘Sign Up’
});
If datalayer is not already installed and set up on your website, we advise getting a developer to set this up.