GTM Data Layer: Complete Implementation Guide
The Data Layer is a JavaScript array (window.dataLayer) that passes structured data from your website to GTM. Push data using dataLayer.push({event: 'event_name', key: 'value'}). GTM reads this data via Data Layer Variables and uses it in tags and triggers. Common implementations: e-commerce transac
Quick Summary
The Data Layer is a JavaScript array (window.dataLayer) that passes structured data from your website to GTM. Push data using dataLayer.push({event: 'event_name', key: 'value'}). GTM reads this data via Data Layer Variables and uses it in tags and triggers. Common implementations: e-commerce transactions (order value, products, currency), form submissions (form name, field values), user properties (logged-in status, user type), and page metadata (page category, content group). Plan your Data Layer schema before implementation — document every event name, parameter, and expected value. Consistent naming is critical.
Overview
The Data Layer is a JavaScript array (window.dataLayer) that passes structured data from your website to GTM. Push data using dataLayer.push({event: 'event_name', key: 'value'}). GTM reads this data via Data Layer Variables and uses it in tags and triggers. Common implementations: e-commerce transactions (order value, products, currency), form submissions (form name, field values), user properties (logged-in status, user type), and page metadata (page category, content group). Plan your Data Layer schema before implementation — document every event name, parameter, and expected value. Consistent naming is critical.
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