About event deduplication

Last updated: February 2025

Event Deduplication is required for advertisers using both the TikTok Pixel and Events API to share duplicate copies of events, which report the exact conversion on their website. If TikTok recognizes that events overlap and are duplicate copies of the exact conversion, we will keep and enrich (see below) the first event to ensure that no double counting of such events will occur for the purposes of measurement and reporting. All deduplicated events are used to help advertisers measure, optimize, and target their ads on TikTok.


To determine if event deduplication is required, please review the following scenarios:

  • Deduplication is not required if an advertiser shares different events separately between the Pixel and the Events API, without event overlap. 

    • For example, sharing AddToCart events through the Pixel, and CompletePayment events through the Events API.

  • Deduplication is required if an advertiser shares the same events through the Pixel and the Events API, with event overlap. 

    • For example, sharing CompletePayment events through both Pixel and the Events API.


How Deduplication Works 

To enable deduplication, developers must ensure the following three parameters are included in the event payload via both Pixel and Events API: 

  • pixel id

  • event (for example, CompletePayment or AddToCart)

  • event_id (a unique string chosen by the advertiser to represent visitor conversion) 


Additionally, we recommend advertisers include the first-party cookie (_ttp) in the event payload. If we do not receive the event_id from the Events API, but receive the TikTok cookie (_ttp), we will attempt to deduplicate between browser/server events based on the _ttp cookie value.


Please follow TikTok For Business Developers' documentation on ways to set up deduplication.


Deduplication Scenarios 

Please refer to the following scenarios and subsequent actions when an overlap occurs between the following:

  • Overlapping between Pixel events

    • We deduplicate any events shared through the Pixel, with the identical event and event_id parameters arriving within a 48-hour window from the first event.

  • Overlap between Events API events.

    • We deduplicate any events shared through the Events API, with the identical event and event_id parameters arriving within a 48-hour window from the first event.

  • Overlap between Pixel and Events API events.

    • We merge events shared by the Pixel and Events API events with the identical event and event_id parameters arriving within 5 minutes of each other and merge extra match keys and parameters into the first event if applicable.        

    • We deduplicate subsequent events shared by the Pixel and Events API events with the identical event and event_id parameters arriving after 5 minutes and within a 48-hour window from the first event.