Dataset ID
A dataset ID is the identifier of the data source an event belongs to - the container that collects events for one business asset so they can be reported, deduplicated, and optimized together. Every event a platform accepts is tied to one; send an event to the wrong identifier and it lands in someone else's container, or nowhere at all.
Meta: the pixel became a dataset
Meta's own checklist for a direct integration is short: a Pixel ID, a Meta Business Suite account, and an access token - and Meta documents that every server event must be tied to a dataset ID, its current name for the object most advertisers still call a pixel. The same identifier serves both channels: the manual setup pairs one Pixel ID for browser and server events, which is precisely what lets event ID deduplication collapse the double delivery.
The same idea under other names
| Platform | Identifier | Where it sits |
|---|---|---|
| Meta | dataset ID (Pixel ID) | Bound to every event; part of the API path |
| Pixel ID | Inside the endpoint URL: .../pixels/<pixel_id>/conversion_events | |
| Snapchat | pixel_id | A required field on web and offline events, so the event lands in the right data source |
| ad account ID | Addressing is by ad account; the Conversions API needs no separate app ID | |
| TikTok | pixel code / data source | Events POST against a data source identifier |
Two operational consequences follow. Credentials and dataset travel together - a token from one organization will not write into another's data source on Snapchat - and a mismatched identifier fails the event outright rather than mis-routing it quietly, so an event rejected for the wrong pixel usually means a configuration value, not an API problem. Where the identifiers come from and how the tokens pair with them is in the Facebook pixel ID and access token guide.