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Optimizely Knowledge Base

Metrics in Optimizely

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  • Develop an overview of how metrics work in Optimizely
  • Begin to formulate a strategy for working with metrics in your experimentation program

In Optimizely, a metric is a quantitative measurement of a visitor action. They are what Optimizely uses to measure differences in visitor behavior that occur as a result of changes you make to your site. Metrics measure the success of your experiment by telling you whether an experiment is winning, losing, or inconclusive.

Metrics are created out of events, which directly track actions like clicks, pageviews, form submissions, purchases, and scroll depth. After you create an event and add them to an Optimizely experiment or Personalization campaign, you'll decide how it's displayed as a metric.

This difference might seem a little vague at first, so let's consider a simple example. Suppose your site has an Add-to-Cart button. You would use an event to count the number of clicks on the button itself. You would use a metric to track something like unique conversions per visitor for visitors who actually click the button and add an item to their carts. 

You can have an event without a metric, but you cannot have a metric that is not based on an event.

Every Optimizely experiment needs at least one metric. You can add or modify metrics at any time. View the metrics attached to your experiment on the Results page

Check out our article on the difference between goals, events, and metrics for a more in-depth explanation.

Identifying the right metric is a huge factor in determining whether your experiment will have statistically significant results. Read our article on choosing primary vs. secondary metrics.

Optimizely lets you choose from several different metric templates, based on what you plan to measure in your experiments. Read our article on when to use each type of metric.

When you're ready to start working with metrics, see our article on adding metrics to an experiment in Optimizely.

And of course, if you run into trouble, check out our article on troubleshooting metrics in Optimizely.