Somewhere inside ChatGPT there is a list of things it has decided you are interested in. Not your chat history. A separate list, written about you, that you did not fill in.
It sits under Settings, then Ad Controls. Until this week, most people had no way to look at it.
The panel surfaced publicly the week of August 24, the same week ChatGPT ads opened in 31 European markets. Ads run on the Free and Go tiers, for logged-in adults. The US test started back in February, so if you have been on a free account since winter, that list has had about six months to fill itself in.
Open the panel and you get three things: an Ads History log of what you have been shown, an Interests list of what the system has inferred about you, and two toggles. Read the Interests list before you touch anything else. It is the part that will actually surprise you, and switching things off first costs you the chance to see it cold.
Two things about that panel are easy to get wrong, and both are the kind of wrong where you believe you are finished and you are not.
The first is the toggles. There are two and they are independent. "Personalize ads" controls whether your activity is used to target what you are shown. "Past chats and memory" controls whether your conversations and saved memories feed that targeting. Turning off one does not turn off the other. Most people will flip the one with the word ads in it, feel done, and leave the second one running.
The second is deletion. Your ads data, meaning Ads History and Interests, is stored and deleted separately from your general ChatGPT data. Clearing your chat history does not clear your ads profile. The obvious cleanup step, the one most privacy advice hands you, leaves that list exactly where it was.
One expectation to reset before you start. Opting out changes which ads you see, not whether you see them. Ads run on Free and Go, so the real off switch is a paid plan or fewer messages a day.
Four checks. Each one takes about a minute.
Settings, then Ad Controls. Do this before you touch a toggle. You are looking for categories you never asked for and would not have guessed.
Same panel. This stops your activity being used to choose what you are shown. It does not stop the ads.
It is its own switch in the same place. If you only did step two, your conversations and memories are still feeding the profile.
Ad data has its own delete control. Use it. Wiping chats will not do this for you, and the list starts rebuilding from the moment you finish, so this is the one to put a reminder on.
There is a reason to do this now rather than in November. On August 19 the FTC opened a comment period on a proposed policy statement saying businesses that use your personal data to set your price, without disclosing it, may be violating the FTC Act. It is a proposal and not a rule, and the comment window closes September 18. It is also the first US federal move to treat "the system knows what you will pay" as a possible deceptive practice, and it landed in the same fortnight your chatbot started showing you its list.
Two quick ones while you are in the settings. Gemini users, the same audit exists under a new name: "Gemini Apps Activity" is being renamed "Keep Activity." And OpenAI retired o3 from ChatGPT on August 26 at the end of its 90 day sunset, so if you had a saved workflow pinned to that model, check whether it still runs.
A simple rule: your ad profile is a separate account. Deleting your chats does not touch it, and one toggle is never both toggles.
If you open that Interests list and find something on it that makes no sense at all, hit reply and tell me what it said. I want to know how strange these get.