### Definition

**Effective reach** is defined as the number of people or the percentage of the audience that receives an advertising message with a frequency equal to or greater than the effective frequency. That is, effective reach is the population receiving the “minimum” effective exposure to an advertisement or campaign.[1]

### Purpose

The purpose of the “effective reach” metric is to measure the portion of an audience exposed to an advertisement enough times to be influenced. Many marketers believe their messages require repetition to “sink in.” Advertisers, like parents and politicians, therefore repeat themselves. But this repetition must be monitored for effectiveness. Toward that end, marketers apply the concepts of effective frequency and effective reach. These concepts assume that the first few times people are exposed to an ad, it may have little effect. Only when more exposures are achieved does the message begin to influence the audience.

### Construction

Effective reach can be expressed as the number of people who have seen a particular advertisement or the percentage of the population that has been exposed to that advertisement at a frequency greater than or equal to the effective frequency.

**Effective Reach** = *The number of people or percent of population **reached with frequency equal to or greater than effective frequency.*

### See also

### References

- ^ Farris, Paul W.; Neil T. Bendle; Phillip E. Pfeifer; and David J. Reibstein (2010).
*Marketing Metrics: The Definitive Guide to Measuring Marketing Performance (Second Edition).*Upper Saddle River, New Jersey: Pearson Education, Inc.