Reach (advertising)

Additions, clarifications, extended definition

In the context of advertising, reach is a fundamental pillar of media planning and campaign evaluation. Reach is in the vast majority of cases expressed as an absolute number, or as a percentage of the target population.

In television and radio, reach is measured using peoplemeters and expresses what percentage of the population saw the advertisement at least once during a given period.

In online advertising, reach is modelled using user IDs and cookies, or logged-in accounts.

In print, outdoor and other traditional media, it is estimated from data on readership, footfall or passers-by at a given site.

Interpretation

The higher the reach, the wider the share of the target group that encountered the campaign.

Watch out: limits and risks of distortion

• Reach must never be added up – neither across different campaigns nor across platforms. For example, reach from television, online advertising and print cannot simply be summed, because the audiences of the individual media often overlap.
• Reach modelling always carries a degree of distortion.
• In the online environment, results can be affected by the limitations of analytics cookies, duplicated users, shared devices or errors in cross-device measurement.
• In offline media, figures are based on panel data or estimates that carry statistical imprecision.
• Reach also says nothing about attention or perception — the fact that a person was exposed to an advertisement does not mean they actually noticed or remembered it.

Where and how to measure

• In the online environment, reach is measured using the analytics tools of the individual platforms – for example Google Ads, Meta Ads Manager, LinkedIn Campaign Manager, TikTok Ads Manager or YouTube Studio.
• In television and radio in the Czech Republic, reach measurement is provided by the Association of Television Organisations (ATO) in cooperation with Nielsen, using a household panel equipped with peoplemeters.
• In print, outdoor or cinema advertising, reach is estimated from readership, footfall or the frequency of passers-by at the sites, as provided by media houses or agencies.

Context

From a campaign evaluation perspective, reach is usually part of media reports, where it is complemented by other indicators – particularly frequency, CPM and GRP. Together they provide an overview of the overall scale and intensity of the delivery of the advertising message.