The Reach Calculator estimates how many unique people saw content when total impressions and average frequency are known. It is useful for campaign summaries, media planning, and audience reporting when a platform provides exposures but the unique audience must be approximated.
Because frequency is an average, the result is a planning estimate rather than a reconstruction of person-level delivery. The page also shows the implied repeat impressions and the share of impressions attributable to repeated exposure.
Use the total number of content or ad exposures for one campaign and period.
Use the average number of impressions delivered per reached person.
Enter the addressable target population to estimate penetration.
Compare estimated reach with repeat impressions to understand breadth versus exposure depth.
Where:
Assumptions: Frequency is assumed to describe the same impressions, campaign, platform, and date range.
Because frequency is an average, the result is a planning estimate rather than a reconstruction of person-level delivery. The page also shows the implied repeat impressions and the share of impressions attributable to repeated exposure.
Reach is estimated from average frequency and may differ from platform-reported unique reach.
Given:
Calculation:
Reach = 360,000 ÷ 3 = 120,000 people. Repeat impressions = 360,000 − 120,000 = 240,000. Penetration = 120,000 ÷ 200,000 × 100 = 60%.
Result: Estimated reach of 120,000 people
Interpretation: The campaign reached about 60% of the entered audience, with two-thirds of impressions representing repeat exposures.
Not always. Platform reach may use identity resolution, deduplication, and proprietary rules. This estimate only divides impressions by average frequency.
A true average frequency for reached people is normally at least 1. Values below 1 usually indicate mismatched definitions or periods.
The mathematical estimate can, but that suggests the target audience figure, frequency, or scope is inconsistent. Review the inputs before interpreting penetration.
Only if you accept that the same people may be counted on multiple channels. Cross-channel unique reach requires deduplication data.
Reach counts unique people, while impressions count every exposure, including repeated views by the same person.