Tag Assistant debug mode announcements

The new Tag Assistant allows you to verify and troubleshoot tagging for global site tag (gtag.js) and Google Tag Manager installations for Google Analytics, Google Ads, and more.

More changes are coming in the form of additional diagnostics and data insights. The existing Tag Assistant chrome extension will pair with the web-based Tag Assistant to offer additional functionality.

Why did Tag Manager’s preview mode change?

Tag Assistant is the evolution of Tag Manager's preview mode. It includes fundamental changes required for it to work with modern browsers while also introducing features to solve some of the most common user pain points.

Previously, Tag Manager preview mode relied on third-party cookies. Modern browsers now restrict the use of third-party cookies, and some block third-party cookies altogether. Google Chrome recently announced plans to make third-party cookies obsolete in the near future. Without third-party cookies, the previous version of Tag Manager preview mode no longer works.

Tag Assistant is designed to work without third-party cookies or extensions. This ensures that you can preview and debug your Tag Manager containers across browsers and devices. Instead of using cookies to turn preview mode on and off, Tag Assistant uses a new homepage at tagassistant.google.com to enable preview mode. As a result, when you use Tag Manager’s preview mode, you will now see two windows: a Tag Assistant window, and the window that you're testing. We’re continuing to improve the experience and introduce new features to help you do even more to debug your containers and improve your tagging.

New Features in Tag Assistant

  • Multi-Page Debugging - Tag Assistant now operates in a standalone window, allowing you to debug multi-page flows. It also works across different browsers and on mobile devices. And, by having the debug content in a separate window, it provides a smoother experience for many websites.
  • Unified debugging of gtag.js and Tag Manager - The new Tag Assistant supports domain-level debugging of gtag.js and Tag Manager. By placing an entire domain into debug mode, all diagnostic information for your tag Manager container and Google tags can be inspected in the same session.
  • More detailed and accurate debugging information - the new Tag Assistant provides more debug insights including API calls that trigger tags, human-readable hit information, and visibility into automatically-emitted Google Analytics enhanced measurement events.
  • Future-proof functionality - The new Tag Assistant uses new infrastructure to maintain functionality as the use of third-party cookies degrades.

To use the new Tag Assistant, visit tagassistant.google.com