Cookie syncing
Cookie mapping (also known as cookie syncing) is the process of associating your platform's cookie ID with the corresponding The Trade Desk cookie ID. This enables both platforms to recognize the same user by their respective IDs.
Choose a tag
The Trade Desk offers two tags for cookie mapping.
Real-time ID tag (recommended)
/doc/CookieRealTimeIDTag
Fetches a user's TDID and writes it to a first-party cookie for server-side tracking with the Real-Time Conversion Events API. Returns the TDID in real time without requiring you to host any redirect infrastructure.
Match tag
/doc/CookieMatchTag
A small piece of code provided by The Trade Desk that is placed on a website or within ads to enable cookie mapping. Returns stored TDIDs in bulk.
Compare the tags
Here's what you need to know about the differences between both mapping tags:
| Capability | Real-time ID tag | Match tag |
|---|---|---|
| Does it recognize the same user across The Trade Desk and your platform? | Yes | Yes |
| Does it return the user ID in real time? | Yes | No |
| Does it require redirect hosting? | No | Yes |
| Does it require storing TDIDs and sending them back to The Trade Desk using Data APIs? | No | Yes |
| Does it support GDPR consent? | Yes, if the tag is modified | Yes |