Click ID

A click ID is a unique string -- typically a long alphanumeric token -- that is generated and appended to the URL when a user clicks an affiliate link. This identifier follows the user through the conversion funnel, from the initial click through to registration, deposit, purchase, or any other qualifying event. When a conversion occurs, the click ID is passed back to the tracking platform via a postback, allowing the system to attribute that conversion to the specific click, affiliate, and campaign that generated it.

Click IDs are the foundation of accurate server-to-server (S2S) tracking. In a typical flow, the tracking platform generates the click ID, the operator's site captures and stores it (usually in a session or database record), and when a conversion event fires, the operator's server includes the click ID in the postback URL. Without a valid click ID, the tracking platform cannot match the conversion to its source. This is why proper click ID capture and storage on the operator's side is one of the most critical technical requirements for affiliate program setup.

Click IDs also serve as a forensic tool for troubleshooting attribution discrepancies. When an affiliate reports a conversion that the operator does not recognize, or vice versa, the click ID provides a traceable record of the original interaction. Teams can follow the click ID through each stage of the funnel to identify where a breakdown occurred -- whether the ID was not captured, not stored, or not passed back correctly. Combined with sub-IDs, click IDs give affiliates granular insight into which traffic sources and campaigns are generating conversions.