Active Users in GA4 represents the number of distinct users who engaged with your website or app during a specified time period. A user is considered "active" when they trigger an engagement session, which occurs when they stay on your site for 10 seconds or longer, have a conversion event, or have 2 or more page or screen views. This metric provides a foundational understanding of your audience size and engagement levels, replacing the traditional "Users" metric from Universal Analytics with a more engagement-focused approach. Unlike simple visitor counts, Active Users emphasises meaningful interaction with your content, filtering out users who immediately bounce or show no genuine interest in your site. This makes it a more reliable indicator of your actual engaged audience size.

Ad Clicks, or simply Clicks, is a marketing metric that counts the number of times users have clicked on a digital advertisement to reach an online property.

Ad Cost per Goal Conversion is the amount of money spent on an ad that leads to a goal conversion. It is used to measure the investment in a single advertisement required to achieve a set goal.

Ad Frequency is the average number of times your ad is displayed to a unique user. It is calculated by dividing your ad’s impressions by its reach. This metric helps understand how frequently your ad is viewed by your target audience on average.

Ad Impressions (IMPR) is a count of the total number of times digital advertisements display on someone’s screen within the publisher's network.

Ad Reach is a count of the number of people who viewed your ads at least once. Reach can help you understand how many people have been exposed to a specific advertisement or marketing message.

Ad Revenue is a digital marketing metric that measures the total amount of money generated from ads displayed on your website or in your app. This includes revenue from third-party sources as well as Google AdMob.

Ad Set Clicks is the total number of times users clicked on a digital advertisement within an ad set. An ad set is a grouping of ads organized by theme.

Ad Set Impressions is the total number of times digital advertisements within an ad set are shown. An ad set is a grouping of ads organized by theme.

Ad Spend is the amount of money spent on specific ad variations within a specific campaign or ad set. This metric helps regulate ad performance.

Ad Unique Clicks is a count of the number of people who clicked on your digital advertisement at least once. This is different than Ad Clicks or Total Clicks, because this is a count of the unique people who clicked.

Advertising Costs is a broad expense category, which typically includes online, broadcast, print, outdoor, and direct mail efforts. Advertising can be used at various stages of the customer journey, from brand awareness and brand shaping, to highly targeted campaigns that are meant to engage existing customers.