What Is Google Tag Manager and Why Do We Recommend It?

You’re starting an advertising campaign, and your marketing agency sends you a block of code with a request: “Please add this to your website.”

Or perhaps you’re setting up your own ads, and Facebook or Google asks you to install a “pixel” or “tracking tag.”

This is a common request we receive from clients. These codes help measure what happens after someone visits your website or clicks an ad. But rather than adding every new tracking code directly to your website, we usually recommend managing them through Google Tag Manager, often shortened to GTM.

Here’s what that means, and why it makes managing your website easier.

What are tracking codes and pixels?

A tracking code is a small piece of code that sends information about activity on your website to a service such as Google Analytics or an advertising platform. You may also hear it called a “tag” or a “pixel.”

Depending on how it’s set up, it might help you understand:

• How many people visit your website.
• Which advertising campaigns bring visitors to it.
• Whether someone completes an enquiry form.
• Whether an ad leads to a purchase.

You don’t need to understand the code itself. What matters is knowing what it’s for, who manages it, and whether it’s still needed.

Think of Google Tag Manager as a folder

Imagine keeping your tracking codes in one organised folder.

We connect that folder to your website once. Your marketing team can then add, update, or remove supported tracking codes inside it, usually without needing to edit the website’s code each time.

Google calls this folder a container.

That’s the basic purpose of Google Tag Manager: it gives you a central place to manage tools such as Google Analytics, Google Ads tracking, and third-party advertising tags. Google’s overview of Tag Manager

For a WordPress website, the GTM container may be connected through a plugin, such as  GTM for WordPress, which is very easy for website administrators to check and update or change if needed, without knowing or accessing code. Alternatively, your website manager can add the GTM code snippet to the website theme code.

Is GTM the same as Google Analytics?

No, although the names make them easy to confuse.

Google Analytics provides reports that help you understand how people find and use your website.

Google Tag Manager manages the tags that send information to tools such as Google Analytics.

You can use GTM to set up Google Analytics tracking, but you still go to Google Analytics to view those reports. Google’s guide to setting up Analytics in Tag Manager

Why not just add each code to the website?

You can install tracking codes directly, and sometimes that’s appropriate. The difficulty is managing them over time.

Imagine your business runs ads with one agency, changes agencies a year later, and then starts managing some campaigns in-house. Each team provides new tracking code.

If those codes are added in different places, perhaps a WordPress plugin, the website’s theme, and individual pages, it becomes harder to answer simple questions:

• Which codes are still active?
• Which advertising accounts do they belong to?
• Are any of them doing the same thing?
• Can an old code be removed?
• Who has access to make the change?

Old tracking can remain long after a campaign or agency relationship ends. Updating it may require someone with access to the website’s code.

Keeping tracking organized in GTM makes it easier to review what’s there and manage changes. It still needs maintenance, but there’s a clear place to start.

Does a new agency need a new GTM container?

Usually, no.

If your website already has a GTM container, a new advertising pixel can generally be added to that existing container, even if it belongs to a different advertising account.

Think of it as adding another document to the folder you already have. You don’t normally need to connect a second folder just to add something new.

Multiple containers can be appropriate in more complex setups, but they can also make oversight harder. If the same tracking is configured in both, the same activity could be reported more than once.

Our usual recommendation is to give the person managing the new tracking appropriate access to the existing container, then have them add and test it.

What should you do when someone sends you code?

First, ask what the code is for.

A snippet labelled “Google Tag Manager”, with an ID such as GTM-XXXXXX, connects a GTM container to your website. A snippet labelled “Meta Pixel Code” installs tracking for Meta’s advertising tools, including Facebook and Instagram.

Those are different requests, even though both arrive as a block of code.

Before installing anything, ask your website manager or marketing team to:

1. Check what’s already installed. Your website may already have GTM or the requested tracking.
2. Confirm which account the tracking belongs to. Your business should retain access to the accounts it relies on.
3. Use the existing container where appropriate. Many new tags can be managed there.
4. Test before publishing. GTM includes a preview tool for checking whether tags work as expected. Google’s guide to verifying and publishing tags

If existing tracking is being moved into GTM, the old installation also needs to be accounted for so it doesn’t continue sending the same information twice.

The main benefit is control: your tracking is easier to find, update, test, and remove when it’s no longer needed.

Will we still need help with tracking?

Basic tracking may be straightforward. Tracking particular forms or other detailed actions can require help from your marketing agency. (Note: DesignTLC does not offer digital marketing, tracking set up/configuration or ongoig analytics.)

Our recommendation

Set up GTM if you plant to or begin more detailed event tracking in GA, or if you run digitail marketing campaigns in Google and/or Meta. Make a note of the GTM tracking code and ensure you have access to manage it. Have your website manager connect the website to the GTM account using a plugin like GTM for WordPress.

That gives your business a more manageable setup as campaigns, agencies, and marketing tools change.