Reach

Each person counts only once, however often they see the advert. It is therefore also called net reach.

For screens, reach is usually estimated, since nobody can identify every passer-by individually. It is based on footfall counts, traffic and passenger data, surveys and models. For a campaign on twenty screens in a city, this gives, for example, the share of residents who passed at least one of them within two weeks. The total of all impressions without deducting repeat contacts is called gross reach.

Operators should not confuse reach with impressions: many impressions among few people produce a high contact frequency but low reach. Figures are only comparable if the method, period and population are stated. The reach of a site is an estimate, not a measured value like an ad play.