Matching users using Unified ID

Unified ID (formerly known as is a free, cookie-based identifier for ad tech providers. At Index Exchange (Index), publishers can enable the Unified ID RTI adapter in their IX Library to match users using the Unified ID. This adapter only calls for the Unified ID if it is not found in the local storage and returns an identifier to the IX Library, which will be passed down to DSPs. For more information on enabling the Unified ID RTI adapter, see Enable a Universal ID provider in the IX Library.

By including a user's Unified ID in the bid request, DSPs can maintain a higher match rate with ad tech platforms while making fewer network calls. Higher match rates allow DSPs to see more users to bid on. These users that have potential to see an ad campaign are usually referred to as an addressable audience. By increasing the addressable audience that a DSP can see for a publisher, DSPs can find more eligible users and facilitate an easier path to achieving buyer budgets and performance goals. DSPs that bid more frequently results in an increase in bid density and publisher revenue.