Troubleshoot experiments

Common issues

• A metric is not tracking correctly – If you see few or no conversions, check the Optimizely Experiment Results page. See, Metrics do not track correctly.
• Your page loads slowly, or you see flashing or flickering – If your original content displays for a moment before the variation, see how to Fix the flashing or flickering variation content.
• Your variation content does not display on your live site – If you are not seeing the changes you expect, see Cannot see the variation.
• You are not seeing a variation that you expect – Use the JavaScript API to check the variation into which you are bucketed, or the log to see whether you qualify for the audience.

See also Experiment not activating and No traffic in the experiment.

Test utilities

If things do not look right, the following resources can help you diagnose the issue:

• Preview tool – Helps you check the functionality of your experiments and campaigns, including how visual changes look for different audiences and when events fire.
• JavaScript API – Helps you verify what live experiments and campaigns are running on a page and which variation you are bucketed in.
• Network console – Helps you verify whether events in a live experiment or campaign are firing correctly. Use it to check that metrics are tracked correctly on the Experiment Results page.
• Optimizely Web Experimentation log – Helps you diagnose more difficult issues in a live experiment or campaign. It tells you whether an experiment or campaign activates on the page, whether you qualify for an audience condition, and whether changes on a page are applied.
• Optimizely Web Experimentation's cookies and localStorage – Uniquely identify visitors, track their actions, and deliver consistent experiences across page loads.