How to fix gtm audit on BigCommerce
Install Google Tag Manager on your store and configure GA4 with ecommerce event tracking (view_item, add_to_cart, purchase) so you can measure what's driving revenue.
Steps for BigCommerce
- In BigCommerce Admin, go to Storefront → Script Manager → Create a Script.
- Set Location to 'Head', Pages to 'All Pages', and paste the GTM <head> snippet. Create a second script with Location set to 'Body' for the <body> snippet.
- For ecommerce dataLayer events, install the 'Pixel Manager for BigCommerce' app from the BigCommerce App Marketplace, which pushes GA4-compatible ecommerce events automatically.
- Alternatively, edit your Stencil theme's base.html (via Stencil CLI or Theme Editor) to add the GTM snippets and custom dataLayer pushes on product, cart, and order-confirmation pages.
- Configure GA4 tags in GTM, verify with Preview + DebugView, and publish.
<!-- GTM Head Snippet — paste inside <head> -->
<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-XXXXXX');</script>
<!-- GTM Body Snippet — paste immediately after opening <body> -->
<noscript><iframe src="https://www.googletagmanager.com/ns.html?id=GTM-XXXXXX"
height="0" width="0" style="display:none;visibility:hidden"></iframe></noscript>
<!-- Example GA4 purchase dataLayer push (server or theme renders this on order-confirmation page) -->
<script>
window.dataLayer = window.dataLayer || [];
dataLayer.push({
event: 'purchase',
ecommerce: {
transaction_id: 'T_12345',
value: 59.99,
currency: 'USD',
items: [{
item_id: 'SKU_001',
item_name: 'Blue Widget',
price: 29.99,
quantity: 2
}]
}
});
</script>What is gtm audit?
Google Tag Manager (GTM) is a free tool from Google that lets you add and manage marketing and analytics scripts on your website without touching code every time. Inside GTM, you install Google Analytics 4 (GA4) along with ecommerce event tracking — signals that fire whenever a shopper views a product, adds something to their cart, or completes a purchase. Think of GTM as a control panel for all the measurement tags on your store, and GA4 as the reporting dashboard that tells you exactly what those shoppers did.
Without GTM and GA4 ecommerce tracking, you are flying blind: you cannot see which traffic sources, products, or promotions actually generate sales. This means you risk wasting ad budget on campaigns that don't convert, missing opportunities to fix high-abandonment checkout steps, and losing the ability to build remarketing audiences for Google Ads and Meta. GA4's purchase data also feeds Google's Smart Bidding algorithms — without it, paid campaigns perform significantly worse, directly costing you revenue. Many regulations and platform policies also require transparent data practices, so having a properly managed tag infrastructure keeps you in control of what fires on your site.
See the complete Gtm audit guide for every platform and the full background.
Not sure if your BigCommerce store has this?
Run a free SEOLZ audit — we’ll find gtm audit and every other issue across your whole site.
Scan my site free