About Our Data

Quantcast has built powerful statistical technology to help you best understand and reach digital media audiences. Our tools enable the direct-measurement of traffic and audience characteristics, empowering both publishers and marketers to operate in a more connected and transparent way throughout strategy, buying, selling and evaluation phases of a campaign.

Direct Measurement

In a major advancement over traditional panel-based measurement methodologies, Quantcast couples machine learning with massive quantities of directly measured data to deliver detailed audience data in real-time for all forms of digital media including websites, video, widgets and advertising campaigns.

Quantcast Measure delivers syndicated online traffic measurement data in compliance with IAB measurement standards.

Anonymity and Relevance

Quantcast only models anonymous records of Internet usage. Quantcast does not intentionally collect any personally identifiable information – that is, information that could be used to uniquely identify or locate an individual. For further information, please see our privacy policy.

Consumers benefit from these tools because the products and services presented to them in online ads are more relevant to their interests. As an example, our tools can determine that because of the content you have viewed online, you (as an anonymous user) may be interested in a specific kind of bicycle. Rather than viewing repetitive, disruptive ads about irrelevant products, you may see ads that showcase a bicycle you may be interested in. Because our audience models evolve constantly, end users see ads that are particularly relevant. In this way, ads work best for both consumers and advertisers, and when they work well for advertisers, publishers can generate more revenue for the content they produce, enabling them to create more great free content for web audiences.


Quantcast provides the most accurate traffic and audience data both on a global and local basis, with audience insights for digital media for every country around the world.

People Versus Cookies

Quantcast provides audience data for both unique cookies counts and people. The Quantcast statistical direct measurement model takes into account numerous factors to build a translation of cookies to people that is unique to each digital media property.

The model was introduced in June 2008 and is detailed in our white paper, Cookie Corrected Audience Data.

Audience Data

Quantcast provides worldwide audience and demographic data for millions of media destinations, websites, videos, widgets, blogs, and advertising campaigns. Though we welcome all digital media publishers and marketers to directly measure their media assets with our services at no cost, some have not yet done so. In our public audience profiles, websites that are Quantified use a Quantcast pixel and therefore are directly measured (see above).

As a courtesy, Quantcast provides rough audience estimates for other digital media properties. These rough estimates are just that – far from perfect. We strongly recommend that publishers refine the accuracy of our reporting by using our measurement services at absolutely no cost.

Learn more about our statistical direct measurement methodology.