How duplicate conversions are prevented
Trackdesk uses the External ID parameter to prevent duplicate conversions.
This ensures that repeated events, such as page reloads or duplicate requests, do not create multiple conversions for the same transaction.
How deduplication works
Deduplication is based on a combination of:
Conversion type
External ID
This means that:
The same External ID can be used across different conversion types
But within the same conversion type, the External ID must be unique
If a conversion is sent with a combination that already exists, the request will fail and be recorded in the Conversion error log.
Network tenants
For Network tenants, deduplication also includes:
Revenue origin ID
In this case, the uniqueness is determined by the combination of:
Conversion type
External ID
Revenue origin ID
Example: page refresh scenario
If you pass an order ID as the External ID:
A user completes a purchase → conversion is created
The user refreshes the thank-you page → same External ID is sent again
Trackdesk rejects the duplicate → no additional conversion is created
This prevents duplicate tracking caused by repeated events.
What is the difference between External CID and External ID?
External CID
Used for click identification and pairing
Similar to Trackdesk CID, but provided by your system
Can be set via script or API
Allows conversions to be attributed using your own identifier
External ID
Used for conversion identification and deduplication
Should be unique per conversion (within the deduplication scope)
Commonly set as:
Order ID
Transaction ID
Payment ID
Also used when updating conversions via API
💡 Summary
External ID prevents duplicate conversions
Deduplication is based on:
Conversion type + External ID
(+ Revenue origin ID for Network tenants)
External CID is used for tracking/attribution, not deduplication