Google Tag


The Google tag (gtag.js) is a single tag website users add to their website to use a variety of Google products and services rather than managing multiple tags for different Google product accounts.  The Google tag is used across the website user’s entire website and connects the tag to multiple destinations.

Previously, users had to set up a global site tag (gtag.js). The global site tag has evolved into the Google tag.

The Google tag sends data from the user’s website to Google product destinations, which helps measure the effectiveness of the user website and ads.  The Google tag is used for tracking and analytics; It collects information regarding website visitors and the actions they take on the site.  The all-in-one functionality of the Google tag keeps maintenance levels low, while

It is important to note:  As website technologies (ex: cookies) continue to change – privacy, browser, or regulation changes – having high-quality, site-wide tagging across a website is critical to ensure the most accurate measurement.

A new “Google tag” screen replaces the existing global site tag screens in Google Ads and Google Analytics, letting users access measurement features without adding code after the initial set-up. If users change settings in the Google tag, all associated destinations are impacted.

How Google Tag works

MetaRouter syncs certain IDs - Google Click ID’s, first-party IDs, and Measurement ID – as minimally as possible to preserve the benefits of the GTag. MetaRouter stores Client IDs as first-party cookies. If MetaRouter does not find the cookie, it creates a Client ID that fires a Gtag first-party library sync. MetaRouter then stores the created Client ID as a first-party cookie and sends it along with events.

MetaRouter’s sync supports the following google identifiers: Client ID (client_id), User ID (user_id_), Google Click ID (gclid), DoubleClick Click ID (dclid), and Match ID (match_id). In order to keep all GTag benefits, all account IDs for Google Ads, Google Analytics (UA/GA4), and CM360 must be added to the MetaRouter UI.

Google cautions that websites should only have one Google Tag. Copying and pasting a new global site tag for each product. Doing this can lead to performance issues and difficulty in code upkeep.

Use Tag Manager’s native tag templates for: Google Ads, Google Analytics, and Floodlight. Once the GTag is set it should not be editable. The GTag defines the scope of the destination IDs for cross-platform measurement.

2024 Updated Options

Send MetaRouterSync to GA4

Default is set to On and should be that way for any client that is not fully aware of the selection. We are leaving the MetaRouterSync on by default as we send the User ID (user_id_) when you added an AW ID in the UI to create a match table. The new option to turn it off will load the gtag and its config on first page load but will not fire the MetaRouterSync event with the User ID (user_id_) and ajs id. We will send these IDs as events are passed but it will not be on first page load.

Enable Google Consent Mode

Google has set new requirements in the EU that requires we send opt-out consent if a user opt-outs vs not just firing the tag. EU users should enable the consent mode so that they do not lose access to Google’s ad networks. With the Consent Mode turned on we will load the tag on an opt-out consent signal from the consent module and send the opt-out signal to Google.


MetaRouter sync’s the anonymous ID to a global Floodlight match ID every 45 days and also syncs when an ad click ID is present in the website URL.


MetaRouter either stores a visitor’s Client ID (GA cookie) if it already exists or generates the visitor’s Client ID if it does not.

Google Tag Benefits

By implementing the Google tag across the website, users gain access to the following benefits for tag management as well as visitor tracking and analytics:

  • Speed: A faster, simpler, and more streamlined implementation and integration with Google products
  • Codeless: Real-time updates, additions, or removals of tags without having to rely on a developer team to code small changes by utilizing measurement features within Google products
  • Future-proof: The latest features and integrations allow users continue measuring visitor actions accurately as advances in technology grow
  • Accuracy: The Google tag achieves more accurate conversion measurements when cookies are not available
  • Versioning: Users can maintain multiple versions of the same tag, which allows for testing or rolling back to a prior version if need be
  • Multiple tags: Google tags provides the ability to condense multiple website tags into one Google tag to receive better visitor data and manage that compiled data in a single place
  • Administration: Google tag allows for management of users and user access to tag settings, separate from access to other products, which gives administrators more control over access to critical measurement settings.