GA4 Audience Definition and Ad Delivery

Master how to define custom audiences in GA4 and deliver targeted ads with precise user behavior triggers.

Ceyhun Enki Aksan Entrepreneur, Maker

Sep 15, 2025

Google Analytics provides us with a highly flexible structure in the context of users and user activities. As mentioned later in this article, only a few of the available features—such as audience-triggered event actions, segments, and comparisons at the audience level—can be transferred to Google Ads for use in retargeting campaigns.

In the article titled GA4 Conversion Events and Ads Transfer, I described the concept of a user completing or fulfilling a specified action as a conversion. In this article, I will similarly define the concept of audience in terms of “value.”

Audience

We could describe an audience as the segmentation of users based on specified actions. These actions may include primary and secondary conversions, as well as related activities (such as time definitions, steps, etc.) created specifically for these conversions. For example, for an e-commerce website, actions such as completing a purchase, adding items to the cart, entering payment and shipping details, and successfully or unsuccessfully processing a payment could be considered. For such scenarios, we can evaluate all users—statically or dynamically—based on dimensions, metrics, and events tied to conversion goals.

I should also mention that, through the segments created in the Discovery reports to analyze user journeys, users can also be segmented¹.

GA4 Audience Creation and Comparison

When Google Analytics detects that user data has been updated or a new user has been acquired, it checks whether the user meets the criteria of any defined audience. Based on the latest data, the user is either added to an audience or removed from one.

In properties that have a Google Ads connection, personalized advertising can be made available to audiences through Google Ads, enabling retargeting campaigns and the creation of similar audience segments for acquiring new users².

Google Analytics 4 (GA4), similar to Universal Analytics (UA), presents all users who have interacted with your website or app under the All Users (All Users) segment. Additionally, if a user has completed a purchase either through in-app or e-commerce, they are included in the Purchasers (Purchasers) audience segment³.

Audiences can also be used for comparisons once they are created. On the other hand, segments can also be defined as audiences.

Audience Creation

You can create an audience from scratch, use templates, or begin by selecting one of the recommended audiences. In order to use recommended audiences, certain conditions (such as meeting all preconditions of the associated estimated metrics) must be met⁴ ⁵.

Depending on the option selected, the defined conditions for evaluating a user within a specific audience must be established. These conditions can be processed statically or dynamically across all sessions, a single session, or a single event.

In a static evaluation, it is sufficient for the user to meet a condition once, whereas in a dynamic evaluation, the condition is re-evaluated each time new information is available, and the user is included if the condition is met (minimum 1 day, maximum 540 days), and excluded if the condition is not met. For static evaluation, we can use users who have completed an in-app purchase, while for dynamic evaluation, we can use users whose products have been added to the cart but who have not yet completed the purchase.

Any point in time or time period can be used within the conditions.

We can use a sequence of actions (indirectly, at any time, or directly in sequence, or at any time interval) for audience criteria.

Transaction Limitations

GA4 provides us with an easy way to create, edit, and archive audiences. However, there are certain limitations. For a single GA4 property, you can create up to 100 audiences (for Google Analytics 360, this limit is 400), but you can send an audience to an unlimited number of targets³. From the moment an audience is created, it begins collecting users who are associated with the metrics, dimensions, and actions defined in the audience. This process may take up to 24–48 hours. The relevant change summary card can be viewed to monitor this.

Sending Audiences to Ads

After linking a Google Analytics 4 property to a Google Ads account, audiences will be automatically transferred. Before audience members can view ads, they must be added to at least one ad group within the audience they joined⁶ ⁷. Transferred audiences can be accessed under the Segments heading. Audiences transferred from different sources can also be listed using the Source filter.

note

For a basic overview, see the articles titled Google Analytics 4 (GA4) Property Structure and Google Analytics 4 - Campaign Management.

Audience-Linked Conversion Setup

When linked to GA4 audience definitions, an event can be triggered when a new user matches the audience definition (for example, a specific number of sessions, page views, adding items to cart, etc.). These events can be used in reports, just like other events, and can be marked as conversions.

When all audience criteria are fully met by a single event, the metadata associated with that event is copied to the triggered event⁸. You can create up to 20 audience-triggered events per property.

Audience Triggers & Conversions in GA4

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