ID5 Help Center

ID5 Javascript Library

Universal ID Overview

The ID5 Universal ID is a shared, neutral identifier that publishers and ad tech platforms can use to recognise users even in environments where 3rd party cookies are not available or blocked. ID5 enables publishers to create and distribute a shared 1st party identifier to the entire ecosystem. Ad tech platforms that connect with ID5 can decrypt the Universal ID and improve their user recognition capabilities. The ID5 Universal ID is designed to respect users' privacy choices throughout the advertising value chain.

How does the ID5 Universal ID work?

By using the ID5 Universal ID, ad tech platforms can eliminate the need to sync their platform-specific IDs with their partners - the equivalent of needing a translator to help two people speaking different languages understand each other. When all platforms are using the Universal ID to transact against, it’s like they’re all speaking the same, common language. After configuring the ID5 JS API, you can make the Universal ID available to any partners on your page via a single Javascript variable. Your partners pass the ID to their platforms via their existing tags/pixels and can use the Universal ID to identity for the user for data collection/aggregation, bidding, optimization, etc., even when third party cookies are not supported.

Javascript API

The ID5 JS API is an open-source library available on Github: All documentation for building and installing the library will be maintained in Github, but please reach out if you have any questions or need help.