Google Optimize will no longer be available after September 30, 2023. Your experiments and personalizations can continue to run until that date. Learn more

Preview mode

Preview your experience variants on multiple devices.

Preview mode allows you to validate that a variant renders as intended before you start an experiment. You can also preview a running experiment.

We recommend using preview mode on Chrome. Safari users must go to Preferences > Privacy and then clear Prevent cross-site tracking to use preview mode. Firefox users must disable Enhanced Tracking Protection using the shield icon available on the browser bar.

Use preview mode

Preview mode allows you to see your experiment exactly as your user would see it. Once you've created a variant, generate a preview by following these steps:

  1. Navigate to the details page of an Optimize experience.
  2. Click Preview.
  3. Select a preview option (Web, Tablet, or Mobile) to open it in a new tab.

Use debug mode

Use Optimize debug mode to review your Optimize experience and its targeting rules before publishing them live. Debugging a variant opens it in a new browser tab, where you can ensure that it renders as you expected.

Note: Read access (or higher) to the container is required to use debug mode. Learn more about Optimize permissions.

To enter debug mode:

  1. Navigate to the details page of an Optimize experience.
  2. Click Preview > Debug.

Debug mode displays the status of your targeting rules so you can achieve more predictable results and higher accuracy. Debug mode is also helpful for troubleshooting experiences because you can see exactly which rules are evaluated as true or false. Learn more about how to debug Optimize experiences.

Use the Chrome extension

When using the Optimize extension in Chrome, you'll see additional features in addition to Web preview and Share preview, mentioned above including Tablet preview and Mobile preview. When previewing a variant, click the Optimize extension icon (to the right of the address bar) to view information about the container, experiment, and variant you're previewing.

The Optimize extension dialog is displayed when previewing a variation.

Exit preview mode

Be sure to exit preview mode so you can go back to viewing the original version of your site. To exit preview mode, click Turn off preview in the extension or on the experiment details page. If the experiment details page shows a blinking preview icon , you're still in preview mode.

Extension icon states

The Optimize extension provides valuable information about the status of the variant you're previewing. The following states are indicated by the icon:

Active previewing state.
Inactive preview page. This occurs when you are previewing a different variant
and the variant in the current tab is no longer active.
No Optimize snippet was detected on the page.
The current page is not being previewed.

Share a preview

On the experiment details page, in the preview options, click Share preview to generate a URL that can be shared with a colleague or stakeholder for review. When the link is clicked, the user enters preview mode. They will similarly need to exit preview mode to go back to viewing the original version of the site. To exit preview mode, click Turn off preview on the landing page of the share preview URL.


Sharing a preview can sometimes generate a blank page. If this happens, close the window and try again in a new window.

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