Conversion events are specific user actions you define as valuable for your business. In GA4, any event can be marked as a conversion by toggling a setting, allowing flexible measurement of what matters most to your goals.
How Conversion Events Work in GA4
GA4 tracks all user interactions as events. When you mark an event as a conversion (now called a "key event"), it appears in conversion reports and can be used for audience building and Google Ads optimization.
The purchase event is automatically recognized as a conversion. Other events require manual configuration. Common conversions include sign_up, generate_lead, add_to_cart, and begin_checkout.
Ecommerce Conversion Events
For online stores, the purchase event is the primary conversion. It captures transaction details including revenue, items, and order ID. This data powers revenue reports and return on ad spend calculations.
track steps leading to purchase. Add to cart events show purchase intent. Begin checkout indicates serious buying consideration. Tracking these intermediate steps helps identify problems before they impact revenue.
Event Types and Limits
GA4 includes automatically collected events like page_view and session_start. Enhanced measurement adds scroll, outbound click, and video engagement events. Recommended events follow Google's naming conventions for common actions. Custom events cover anything else you need to track.
Free GA4 properties allow 30 custom conversions. Predefined events like purchase do not count toward this limit. GA4 360 increases the limit to 50.
Using Conversions for Optimization
Conversion data shared with Google Ads enables Smart Bidding strategies. The platform optimizes ad delivery toward users likely to convert based on your defined events. This connection makes accurate conversion tracking directly impact advertising efficiency.
