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Implementing LiveRamp's Real-Time CID Delivery Tag

The Real-Time CID Delivery Tag enables you to receive a CID (your platform’s custom ID) in real time when you pass us a user’s cookie via a tag you implement on your website. This allows you to recognize a website user from anonymous site activity, and can be used for retargeting, site personalization, or measurement.

When the tag fires with the user’s cookie, LiveRamp uses the anonymized PII (personally identifiable information) we have associated with that cookie and a mapping you provide that maps your CIDs to your users’ personal information to find the CID associated with that cookie and then pass that CID back to you. All PII is anonymized during the matching process.

Real-Time CID Delivery Tags can be implemented via iframe or gif.

Follow the instructions below to set up the necessary components to get up and running.


We understand that not all websites are created alike. Our team is here to support you and your team through the implementation process. Don't hesitate to contact your account rep with any questions.

Implement the Tag

Once your LiveRamp rep has provided you with your tag ID, add the tag below to the header of all pages where you want CIDs returned. These might include the following types of locations:

  • Post-registration pages

  • Post-login pages

  • Returning-user pages

For implementation via iframe:

<iframe src="<TAG ID>.gif"></iframe>

For implementation via gif:

<img src="<TAG ID>.gif">

<script src="<TAG ID>.html"></script>

Upload CID Mapping Files

For LiveRamp to be able to connect the PII associated with the cookies in our identity graph to your CIDs, we need a mapping between your CIDs and your users’ personal information (such as email address, name and postal address (NAP), or phone number). You will need to periodically upload your CID mapping file to LiveRamp, usually on a cadence of every three months.


The tag will redirect to your URL even if we have not made a match and have no data to pass.


LiveRamp will delete all personal identifiers you send after seven days. We will only retain the data sent in a pseudonymous form to ensure consumer privacy.

For information on how to structure your mapping files, see LiveRamp’s file formatting guidelines.

For information on how to upload your data, see “Getting Your Data Into LiveRamp”.

Test the Tag

Once your LiveRamp rep confirms that your CID mapping has been set up, test your implementation.


LiveRamp does not receive any alerts if your tag fails. We will help troubleshoot any tag failures, but you will need to monitor the performance of your tags.

Use the steps below to conduct your audit:

  1. Open a new incognito window.

  2. Cookie yourself as a user using one of the email addresses that you included in the CID mapping file using a publisher pixel.

    1. Get an email address from the CID mapping file.

    2. If the email address is not in MD5-hashed format, first make sure the email address is lowercased and then generate the MD5 version by running in terminal: md5sum <<<""

    3. In the incognito window, enter the URL “<EMAIL_MD5>]” (where "<EMAIL_MD5>" is the MD5 hash of the email address you got from the CID mapping file. Note: You must use "781.gif." Do not use your own tag ID.

  3. Right click on the page and select "Inspect Element."

  4. Go to the "Network" tab to monitor redirects.

  5. Call the referrer URL you provided to the partner:[tag ID].gif. If there is a CID tied to the user from step 2, then you should see the URL called with this CID included.

Maintain the Tag

Whenever you make updates on any web pages that include the tag, make sure that the tag is properly implemented. Notify LiveRamp when web page changes are made so that we can help ensure that the tag continues to function correctly.

The Real-Time CID Delivery Tag is currently a beta product and so we’re actively gathering feedback as we develop tag reporting.