How to fix gtm audit on Shopify

Steps for Shopify

1. Go to Online Store › Themes › and click 'Edit code' on your active theme.
2. Open theme.liquid. Paste the GTM <script> snippet just before the closing </head> tag, and the <noscript> snippet just after the opening <body> tag.
3. For GA4 ecommerce events, install the free 'GA4 & GTM Kit' app (by House of Analytics) or 'Elevar' from the Shopify App Store — both push a complete ecommerce data layer so GTM can pick up view_item, add_to_cart, and purchase events automatically.
4. In GTM, create GA4 Event tags that read from the data layer variables the app creates (e.g. ecommerce.items, event = 'add_to_cart') and publish the container.
5. Verify by opening your storefront in GTM Preview mode and walking through a product page and checkout.

What is gtm audit?

Google Tag Manager (GTM) is a free tool from Google that acts as a "container" on your website — it lets you install and manage tracking scripts (like Google Analytics 4, Meta Pixel, TikTok Pixel, and dozens more) without editing your store's code every time. Right now, no GTM container is detected on your site, which means you are almost certainly missing critical data about how shoppers find, browse, and buy from your store. GA4 ecommerce events are the specific signals (like "viewed a product," "added to cart," "completed a purchase") that GA4 needs to build reports you can actually act on.

Without GTM and GA4 ecommerce tracking, you are flying blind: you cannot see which marketing channels drive real revenue, which products are viewed but never bought, or where shoppers abandon your funnel. Google Ads Smart Bidding and Performance Max campaigns require conversion data from GA4 to optimise spend — without it, you are wasting ad budget. Retailers with proper ecommerce event tracking consistently find 15–30% of ad spend is going to non-converting channels that they only discover through data. Beyond advertising, GA4 audience data powers remarketing lists, personalisation, and Merchant Center signals that directly affect your Shopping and Search rankings.

See the complete Gtm audit guide for every platform and the full background.