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These docs are for v2.0. Click to read the latest docs for v3.0.


A metric is a quantitative measurement of a visitor action. Metrics 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](πŸ”—ο»Ώ), which directly track actions like clicks, pageviews, form submissions, purchases, and scroll depth. After you [create an event](πŸ”—ο»Ώ) and add it to an experiment, you'll decide how it's displayed as a metric.

For example, suppose your site has an Add-to-Cart button. You would use an **event** to track every time the button is clicked. You would use a **metric** to measure the percentage of users who added to cart at least once, or alternatively the average number of items added per user.

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](πŸ”—ο»Ώ) page.

Tip

Check out our support article on [the difference between events and metrics](πŸ”—ο»Ώ) for a more in-depth explanation.

Identifying the right metric is a huge factor in determining whether your experiment will have statistically significant results. See these KB articles:

  • ο»Ώ[Choosing primary vs. secondary metrics](πŸ”—ο»Ώ).

  • ο»Ώ[Types of metrics and when to use them](πŸ”—ο»Ώ).

  • ο»Ώ[Focusing on metrics that matter](πŸ”—ο»Ώ).

When you are ready to start working with metrics, see our article on how to [Create a metric in Optimizely](πŸ”—ο»Ώ). And of course, if you run into trouble, check out our article on [troubleshooting metrics](πŸ”—ο»Ώ).