Reach
The total number of unique users who saw an ad at least once during a campaign period.
What Reach means
Reach measures the number of unique users who were exposed to an advertisement at least once within a given time period. Unlike impressions (which count total views including repeats), reach counts each user only once. Reach is a key metric for brand awareness campaigns and is used alongside frequency to understand ad saturation. Platforms calculate reach using user-level data, which itself is subject to privacy regulations — cross-platform reach measurement has become more difficult as privacy restrictions limit user-level tracking. Meta provides estimated reach during audience selection, helping advertisers gauge potential audience size. From a compliance perspective, reach metrics in Special Ad Categories are affected by targeting restrictions — the required broader targeting for housing, employment, and credit ads typically increases reach but reduces targeting precision.
Related terms
Impressions
The number of times an ad is displayed on a screen, regardless of whether it was actually seen or clicked.
Frequency
The average number of times a unique user sees a specific ad within a given time period.
Audience Targeting
The process of defining which users will see an ad based on demographics, interests, behaviors, and other criteria.
Cost Per Mille
The cost per thousand impressions, a standard pricing model for display and video advertising.