Cost per impression
|Search engine marketing|
Cost per impression, often abbreviated to CPI, is a term used in online advertising and marketing related to web traffic. It refers to the cost of internet marketing or email advertising campaigns where advertisers pay for every time an ad is displayed. Specifically, it is the cost to offer potential customers one opportunity to see the advertisement.
Cost per impression, along with cost per click and cost per order, is used to assess the cost effectiveness and profitability of online advertising. CPI is the closest online advertising strategy to those offered in other media such as television or print, which sell advertising based on estimated viewership or readership. CPI provides a comparable measure to contrast internet advertising with other media.
Impression versus Pageview 
An impression is the display of an ad to a user while viewing a web page. A single web page may contain multiple ads. In such cases, a single pageview would result in one impression for each ad displayed. In order to count the impressions served as accurately as possible and prevent fraud, an ad server may exclude certain non-qualifying activities such as page-refreshes or other user actions from counting as impressions. When advertising rates are described as CPM or CPI, this is the amount paid for every thousand qualifying impressions served.
Cost per impression is derived from advertising cost and the number of impressions.
- Cost per impression ($) = Advertising cost ($) ÷ Number of Impressions (#)
See also 
- Cost per click (CPC)/Pay per click (PPC)
- Cost per order
- Cost per mille (CPM)
- Effective cost per mille (eCPM)
- Cost per action (CPA)
- Effective cost per action (eCPA)
- Click-through rate (CTR)
- Internet marketing
- Compensation methods
- Performance-based advertising
- Conversion rate (CVR)
- What Is CPM-Based Web Advertising?
- Farris, Paul W.; Neil T. Bendle; Phillip E. Pfeifer; David J. Reibstein (2010). Marketing Metrics: The Definitive Guide to Measuring Marketing Performance. Upper Saddle River, New Jersey: Pearson Education, Inc. ISBN 0-13-705829-2. The Marketing Accountability Standards Board (MASB) endorses the definitions, purposes, and constructs of classes of measures that appear in Marketing Metrics as part of its ongoing Common Language: Marketing Activities and Metrics Project.
- AdBalance - Glossary
Further reading 
- Chaffey, Dave; et al. (2006). Internet Marketing: Strategy, Implementation and Practice (3rd ed.). Harlow, England: Prentice Hall. ISBN 0-273-69405-7.