About Google Tag Manager - Before You Begin

To ensure that Google Tag Manager is configured to meet your business needs, consider the following points.

How many accounts are needed? Who should create them?

Set up one account per company. The company for which the tags will be managed should create the account in Google Tag Manager. For example, if an agency manages tags on behalf of an advertiser, the advertiser should create the Google Tag Manager account and then add the agency's Google account as a user. Read Setup and Workflow to learn how to set up an account.

Agencies can manage their clients' Google Tag Manager accounts by signing into their own Google Account (assuming that the clients have followed the best practice of (1) creating the Google Tag Manager account themselves and (2) adding the agency's Google account as a user). Also, multiple users can manage the same Google Tag Manager account, and each user can be given different access permissions by the account administrators. Read Users and Permissions to learn more.

Are you a mobile app developer?

Set up one container per mobile app. Each new major version of your app should have a new container. (Minor updates to an app can use the same container since the config keys will likely be the same or very similar.)

Do you manage multiple domains? (Web)

Typically, you set up one container per web domain. However, if the user experience and tags on a website span more than one domain, it's best to set up a single container that serves all the domains involved. Here are a few considerations:

• Configuration (rules, triggers, and variables) can't be shared across containers. So, if the tags and firing logic is similar across domains, it makes sense to use a single container, because maintaining multiple similar configurations is time-consuming and error-prone.
• Having many tags in a single container can be confusing, and managing the container becomes more difficult. Also, defining too many tags and triggers increases the size of the container and the amount of data that the browser must download.
• User permissions can only be set at the container level. If you need to prevent the administrators of different domains from changing each other's configurations, use a different container for each domain.
• When someone publishes a container, all changes go live, regardless of domain. If you need to apply changes to one domain without affecting other domains, use a different container for each domain.

Read Setup and Workflow (Web) to learn about accounts and containers.

What tags do you have deployed on your website? Where?

Begin by identifying all of the tags you have deployed on your site and where they are deployed (e.g. in global headers or footers, on landing pages, confirmation pages, in response to button clicks, etc.)

Think about what information you want to collect and determine if there are additional tags you want to deploy. If the data you want to collect is not visible on the page, refer to the developer documentation for information on how to pass additional data to tags.

If all of your tags fire as pages are loading, and these pages can be identified by their URLs, a basic container implementation may be sufficient for your needs. Once your Google Tag Manager account and container have been created, simply place the provided container snippet (generated when you create the container) on every page of your website immediately after the opening HTML body tag. Read Setup and Workflow (Web) to learn about containers and the container snippet.

If any of your tags fire on button clicks, events, or specific pages that are indistinguishable by URL, your webmaster may need to customize your container implementation. Refer to the Google Tag Manager developer documentation for more information.

Regardless of whether you need a basic or customized container implementation, plan for a site-wide deployment in which you migrate all your tracking tags into Google Tag Manager at one time. This allows you to take full advantage of Google Tag Manager's benefits. When you want to add or edit tags in the future, you won’t have to retag your site and you can manage all your tag updates using Google Tag Manager.

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