The Quantcast Platform allows you to view insights and target advertising campaigns based on predefined audiences. You can build audiences based on the general internet population, pixels placed on your website, or offline data you have uploaded to the platform.
Two indicators, Index and Composition, are used across all parts of the Quantcast Platform to help you understand your audience. In Audience Planner, these two indicators can help you gain insight into your audience as you build it.
Index
A comparison of the composition of users within this segment in your persona against the composition of users within this segment across the currently selected location.

The Index metric compares your audience size against users within the same segment/category across the Internet.
Across all segments, the US average index is represented as 100. If a segment has an index above 100, your audience is more likely to be in that segment than the US average. Conversely, if a segment has an index below 100, your audience is less likely to be in that segment.

In the example above, we are looking at an audience under the Education category. The Grad School segment shows an index of 115. This means this audience is 1.15x more likely to have a Grad School education than the US average.
Composition
The percentage of this persona that falls into a given Demographic segment across the US Internet, based on unique users.
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The Composition metric shows the likely percentage your audience represents for segments that fall within a given category. Composition will always equal 100% for each category (e.g., Gender) based on your audience size.
In the example above, we are considering the likely Gender category of the audience. The audience composition leans more towards the Female segment, accounting for 52% of the total audience.
For definitions and use cases, click on the Info icon.

Use this report to help you:
Quickly perform audience research for your media plan.
By obtaining a full Demographic profile of the persona you created, you can better demonstrate the value of that persona beyond the base criteria. Use this data to dive deeper into the target audience and share some interesting facts you may not have known. This will set your media plan apart.
Inform your content creation strategy for reaching this audience.
When constructing the story and unique content strategy, leverage these data points to validate and inform your creative team on the target audience’s other interests and characteristics to create more tailored and effective content.
To learn how to build an audience, see Audience Building