Google Click Identifier (GCLID): Definition
Google Click ID (GCLID) is a parameter passed in the URL with ad clicks, to identify the campaign and other attributes of the click associated with the ad for ad tracking and campaign attribution. In Google Ads, this is enabled by turning on the auto-tagging setting. It’s required for Google Ads website conversion tracking and also used to link data between Google Ads and Google Analytics. It can also be used in conjunction with features like offline conversion tracking.
