Custom audiences & lookalikes for ChatGPT Ads

Relevance is the cheapest performance lever there is. With custom audiences you put your ChatGPT ads in front of the people most likely to convert — instead of just anyone.

What is a custom audience?

An audience built from your own first-party data: a list of customers you upload and match against the ChatGPT user base.

Uploading a list

• As a CSV with identifiers like email address and phone number.
• The types are detected automatically (identifier_resolution: auto).
• Data is hashed for matching — you upload contact points, not full profiles.

After upload the matching runs asynchronously: membership is processed and the audience moves from processing to ready.

Lookalikes

From an existing customer list you can build a lookalike audience — people who resemble your best customers. Ideal for winning high-intent reach.

Common uses

• Retargeting: re-engage cart abandoners or newsletter subscribers.
• Exclusion: keep existing buyers out of new-customer campaigns.
• Scaling: lookalikes of high-value customers for cold reach.

In Chatvertise you upload lists, build lookalikes and see the status of every membership job (resumable/cancelable) in one place. Connect your API key and start free.