ID5 Help Center

Data Platforms

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.

Solution Overview

Data Provider to DMP Integration



  1. Publisher first loads its CMP and captures the user’s consent preferences. This is essential before any IDs or ads are requested or delivered
  2. The ID5 API checks in cache (local storage, 1P or 3P cookies) for an ID5 ID and ensures it is still fresh. If necessary, a request to ID5 is made for a new/refreshed ID, which is then placed in cache to avoid unnecessary http requests on future page views.
  3. The DMP tag on the publisher’s page retrieves the ID5 ID from the API and passes it, along with any other data signals they normally send, to the DMP servers for processing
  4. In order to aggregate data and build segments, the DMP must decrypt the ID5 ID with keys provided by ID5, which happens outside of the data ingestion process.
  5. The DMP pushes the generated data segments to Activation Platforms (Data Exchanges, DSPs, SSPs, etc) and includes the decrypted ID5 ID in addition to, or instead of, the normal user IDs they pass
  6. Outside of the data ingestion process, the Activation Platform receives decryption keys from ID5 in order to decrypt incoming requests with encrypted ID5 IDs in order to match them to the data they received in step 5

Data Exchange Integration



  1. Publisher first loads its CMP and captures the user’s consent preferences. This is essential before any IDs or ads are requested or delivered
  2. The ID5 API checks in cache (local storage, 1P or 3P cookies) for an ID5 ID and ensures it is still fresh. If necessary, a request to ID5 is made for a new/refreshed ID, which is then placed in cache to avoid unnecessary http requests on future page views.
  3. The DMP tag on the publisher’s page retrieves the ID5 ID and passes it, along with any other data signals they normally use, to its servers for processing
  4. In order to aggregate data and build segments, the DMP must decrypt the ID5 ID with keys provided by ID5, which happens outside of the data ingestion process.
  5. The DMP pushes the generated data segments to Data Exchange and includes the decrypted ID5 ID in addition to, or instead of, the normal user IDs they pass
  6. The Data Exchange pushes the DMP’s data segments to DSPs and includes the decrypted ID5 ID in addition to, or instead of, the normal user IDs they pass
  7. Outside of the data ingestion process, DSPs receive decryption keys in order to decrypt the ID5 ID on bid requests and match the ID5 ID to their internal ID

ID5 Integration Overview

Integration Phases


Phase 1: Collect & Log

  1. Integrate calls to ID5 API in data collection tags
  2. Listen to the ID5 ID in calls to your platform
  3. Log IDs for analytics purposes

Phase 2: Read & Measure

  1. If applicable, pass through the still-encrypted ID5 ID in raw data feeds to other platforms
  2. Measure potential uplift v. proprietary IDs, broken down by browser type (Chrome v. Safari/Firefox), countries, devices, etc.

Phase 3: Use & Share

  1. Implement real-time decryption and add the ID5 ID to your ID graph
  2. Enable analytics and audience building with the ID5 ID
  3. Use the ID5 ID (in addition to existing IDs) when sending data segments to other platforms

ID5 Integration Details

ID5 Partner Creation

Before getting started with the Universal ID, we need to make sure you have an ID5 Partner account. If you are not already integrated with ID5, reach out to contact@id5.io and we’ll get you set up right away.

Passing or Receiving the ID5 ID in Data Integrations

Data integrations between platforms are custom with no industry standards to go by. As such, you will need to work with your inbound or outbound data partner to determine the best way to receive or pass the ID5 ID with them. However, we’ve experienced some of these integrations and have the following tips and best practices to share.

If you’d like to hear more about how other platforms have addressed this or would like to seek advice, reach out to ID5 at contact@id5.io and we’d be more than happy to provide you some best practices and consulting to help make your integration work

JSON Object

If data is passed using JSON, rather than just pass a field called “id” (which could contain the inbound or outbound partner’s UID), we recommend using (or creating) a user ids array that can contain multiple ids: the receiving partner’s, the sending partner’s, and shared IDs like ID5. An example may look like this:
{
    "user_ids": [
        {
            "source": "RECEIVING_PARTNER",
            "uids": [{
                "id": "RECEIVING_PARTNER_UID"
            }]
        },
        {
            "source": "id5-sync.com",
            "uids": [{
                "id": "ID5-abc123"
            }]
        }
    ],
    ... // additional data fields
}

Flat Files

If data is passed using flat files, typically it is agreed ahead of time whether to use the receiving partner’s or the outbound partner’s UID for all rows of data received, along with a file format for passing data. We suggest adding a field in the file format to accept a shared ID like ID5, in addition to, or instead of, the existing UID being used.

ID Decryption

ID5 encrypts the Universal ID in order to enforce the privacy preferences of the consumer and the publisher. To learn how to decrypt the Universal ID, please visit Decrypting the Universal ID (login required).

Privacy & Regulations

Privacy-by-Design

ID5 has built a privacy-by-design shared ID service for publishers and ad tech vendors. Our service leverages the IAB’s Transparency and Consent Framework (TCF) and US Privacy Framework to capture the user’s privacy preferences.

As a shared ID provider, ID5 acts as a Controller of the Universal ID, and thus, we must receive a valid legal basis to process requests. When we receive a request for the ID5 ID, we check that we have a legal basis to store our user ID in a cookie before proceeding; if we don’t have one, we do not read our cookie or write to it as part of the HTTP response.

When ID5 returns an ID to the page, the value is encrypted in such a way that only platforms that have authorization to process data (based on the consumer’s and publisher’s privacy preferences) are able to decrypt the string back to a stable ID. By doing so, ID5 enforces privacy preferences and regulations, ensuring that no downstream party can understand the ID without the proper legal basis to do so. When the ID is non-decryptable, the request is truly anonymized, preventing any personal data from being retrieved or processed.

Privacy Policy

For our Platform Privacy Policy, please visit https://id5.io/platform-privacy-policy.