# Event deduplication

> Merging the same conversion reported twice, such as by the browser and the server, so it counts once.

Source: https://datacenter.so/glossary/event-deduplication
Also called: dedup, dedupe.

When a browser tag and a server both report a purchase, the receiving tool must know they are one event. Meta merges a browser event and a server event that share the event name and the event id, if they arrive within 48 hours of the first ([Meta](https://developers.facebook.com/docs/marketing-api/conversions-api/deduplicate-pixel-and-server-events)).

The order id is the natural event id, since both the thank-you page and the server know it. Use the exact same string in both places.

## Related terms

- https://datacenter.so/glossary/conversions-api
- https://datacenter.so/glossary/server-side-tracking
- https://datacenter.so/glossary/conversion