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What's the difference between events and metrics

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  • Distinguish between events and metrics

Events and metrics: what's the difference? Both have to do with tracking visitor actions and determining which variations are winning or losing, with some important distinctions.

In Optimizely, you use events to track visitor actions like clicks, pageviews, form submissions, and purchases. Events live on pages, which are reusable URL templates that let you choose where campaigns and experiments run. Each time you create a page, Optimizely automatically creates a pageview event for it, but you can also create click and custom events. Events are always on, and you can track them in any experiment—not just the experiment where you create them—so they help you get experiments and campaigns up and running quickly, which saves you time.

Events are specific to projects. They're listed under Implementation > Events.


After you add events to an Optimizely campaign or experiment, they become metrics. Metrics help you measure differences in visitor behavior based on changes you make to your site in experiment variations or personalized experiences. The event you choose as your primary metric determines which variations are winning and losing.

To find metrics for individual experiments, select an experiment and click Metrics in the Manage Experiment menu.


More resources

Learn more about events in Optimizely or set up an event

Set up a custom event in Optimizely for visitor behaviors that you can't measure in pageviews or clicks