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title: "How to Retarget Using Dynamic Segments via Segment Alternative ID"
canonical: "https://hub.freewheel.tv/space/BC/115179657/How%20to%20Retarget%20Using%20Dynamic%20Segments%20via%20Segment%20Alternative%20ID"
format: markdown
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Table of Contents Overview When retargeting using dynamic segments via segment alternative ID, users can be dynamically added to segments using values from a website, eliminating the need to install a separate pixel for every potential segment. For example, a retailer who wants to pass a brand name or product name (or both) when a user visits a product details page can use this solution to add the user to a specific segment in Buyer Cloud. This feature must be enabled by the Buyer Cloud team. To get started, please reach out to your Account Representative for more information. How It Works Create a New Segment Navigate to Trafficking > Segments > New Segment. Name the Segment Assign a name to the segment as needed. Define the Alternative ID In the Alternative ID field, enter the dynamic value that will be passed to Buyer Cloud for this segment. It’s recommended to use lowercase letters and avoid spaces or special characters to minimize potential issues. If your key-value library includes special characters, Buyer Cloud supports them, but it is advised to do additional QA to ensure proper URL escaping. Select the Tag Type Choose the tag type: Javascript Tag Using Alternative ID to add users into a segment . Save and Generate Tag Click Save & Generate Tag . Note the account_id is a required parameter for this tag, unlike in a standard segment tag. The generated tag will look like this: 
Install the Pixel Install the pixel on the conversion page . Use JavaScript or another technology to dynamically populate the segment alternative ID when the pixel is triggered on the page. The tag will result in a 3XX redirect with additional parameters. Using a Single Segment Tag to Populate Multiple Segments with Alternative IDs The segment tag can be configured to add a user to multiple segment keys within Buyer Cloud. This is done by specifying multiple segment_alt_id parameters in the segment URL. Example of Adding Multiple Segments: 
If a value is needed for each user-segment association, specify the value parameter in the same order as the segment_alt_id parameters. Example with Value Assignments: To assign a value of 1.5 to shamim and 3.6 to ari , use either of the following: Option 1 : 
Option 2 : 
If you want to assign values to only some segments, make sure an empty &value= parameter is included for each segment that does not receive a value. This ensures that the key-to-value order is maintained. The number of value parameters must match the number of segment_alt_id parameters. Limits A user can be added to up to 100 segment keys in a single associate-segment call. This is a hard limit and cannot be increased.