What is Google Tag Manager and how does it work?
Google Tag Manager is a free tag management system from Google that lets you deploy and manage marketing and analytics scripts on your website without editing code directly. You add a single GTM snippet to your site once, then manage all other tags — GA4, Google Ads, Meta Pixel, etc. — through GTM's web interface. Tags fire based on triggers you define, such as page loads, button clicks, or form submissions.
Do I need a developer to use Google Tag Manager?
GTM significantly reduces the need for developer involvement in day-to-day tracking changes. Once the GTM container snippet is installed on your website (which does require development work), most tag additions and updates can be done by a marketer or analyst without touching the site code. Complex implementations — like custom data layers or tracking on single-page apps — still benefit from developer collaboration.
What is a GTM container audit and why do I need one?
A GTM container audit is a thorough review of every tag, trigger, and variable in your GTM container. Over time, containers accumulate outdated tags, duplicate firing rules, and broken configurations from past agencies or campaigns. An audit identifies everything that needs removing, fixing, or updating — and the result is cleaner data, faster page load times, and a GTM container your team can actually understand and maintain.
How many tags should a GTM container have?
There is no fixed number, but a well-managed container for a mid-size business typically has 15–40 active tags. If your container has 100+ tags and no clear naming convention, it almost certainly contains significant bloat from accumulated marketing experiments, abandoned campaigns, and duplicate tracking scripts. Our GTM audit removes what is not needed and organises what remains.
Can GTM slow down my website?
GTM itself is highly optimised and asynchronously loaded, but the tags fired through GTM — especially multiple heavy third-party scripts — can impact page load speed. Migrating tags to server-side GTM, removing unused tags, and using GTM's built-in performance features (like tag sequencing and firing limits) can significantly reduce the tracking-related performance impact on your site.
What is the difference between GTM Preview mode and live publishing?
GTM Preview mode lets you test your tag configuration on your website without affecting real visitors — only you (in the Preview tab) trigger the tags. This lets you verify that tags fire correctly, variables return the right values, and triggers activate at the right moments before pushing changes live. We always test in Preview mode and validate in destination platforms before publishing any changes.
Can I have multiple GTM containers on one website?
Yes, but it is generally not recommended. Multiple containers can cause conflicts, duplicate tag firing, and performance issues. There are legitimate use cases — such as a separate container for AMP pages or a server-side container — but a single, well-organised client-side container handles most website needs. Our audit identifies and resolves conflicts caused by multiple containers.
What happens if I delete a GTM tag by mistake?
GTM maintains a complete version history of every published container version. If a tag is accidentally deleted and the container is republished, you can roll back to a previous version in seconds. We always create a new container version (essentially a snapshot) before making significant changes, so there is always a safe restore point available.
How does GTM handle cookie consent and Consent Mode v2?
GTM has built-in Consent Mode support. You can configure consent requirements for each tag (specifying which consent types must be granted before the tag fires), and GTM will automatically block tags from firing until the user grants the appropriate consent via your cookie banner. We configure this correctly during our GTM setup to ensure full Consent Mode v2 compliance.
What is a GTM data layer and why is it important?
The GTM data layer is a JavaScript array that acts as a communication bridge between your website and GTM. Your website pushes structured data into the data layer — product information, transaction details, user attributes, form field values — and GTM reads these values through data layer variables to feed them into your tags. A well-designed data layer is essential for accurate ecommerce tracking, dynamic conversion values, and any tracking that depends on page-specific data.