Glossary A–ZLetter G
Gross impressions
Gross impressions are the total of all impressions in a campaign, with each person counted as often as they had the chance to come into contact with the advertising.
Someone who walks past a screen five times counts five times. The figure is therefore always at least as large as the net reach.
In screen network offers and reports, gross impressions are the usual measure because they can be calculated from ad plays and the estimated audience per play. An example: a creative plays 1,000 times, and an average of ten people within the viewing area is assumed per play; that gives 10,000 gross impressions. Dividing gross impressions by net reach gives the average number of impressions per person reached.
Gross impressions say nothing about how many different people were reached and nothing about whether anyone looked. A high figure can also mean that a few people were reached very often. In reports, operators should state how the audience per play was determined and should not present gross impressions as the number of people reached.