Visual Website Optimizer (VWO)


Heap automatically captures all VWO active test variations as a property attached to every event on a given page. With Heap's VWO integration, you can answer questions like:

  • How does an A/B test impact long-term retention?
  • Do users exposed to an experiment convert faster than others?
  • Did a given experiment influence behavior that isn’t directly related to the functionality changed?


To get started, simply click CONNECT on the VWO Source page. Once connected, Heap will automatically capture all active experiments and exposed variations as a property on all events for a given page.

Synchronous only support

Heap automatic capture currently only supports the synchronous installation of VWO and requires that Heap is loaded after VWO for proper capture of experiment data.

Data Format

Heap will automatically capture all active VWO experiments and attach a pageview-level property to all events on that page in the user's experience (including custom events). The format of the property follows the pattern of VWO: [Test Name] with the value of [Variation Name]. An example in this format might be: VWO: Home Page Test as the property name and Control as the value. Please refer to your experiment setup in VWO for more info on what these values will contain!

In practice, you'll see additional event-level properties on events where an active experiment is running. In the example image below, you can see a property entitled VWO: Homepage headline test with a value of Variation #1 included.

To use in analysis, simply apply a group by clause to the analysis of interest and specify the event level property with the test property of interest to cut your analysis by the experiment exposed to the user at the time of the event!