Every new channel shows up with the same question attached: is it working, or is it taking credit for something that was going to happen anyway? ChatGPT Ads arrives with a twist. People ask, compare, and decide inside one conversation, and then convert somewhere else entirely. Your last-click report is going to be very confused.

Why attribution struggles here

OpenAI reports impressions, clicks, CTR, CPC, CPM and spend. Useful numbers. None of them tell you whether the sale would have happened without the ad. Conversational discovery does most of its work before anyone clicks anything, which means the credit lands on branded search, direct, or whatever touchpoint happened to be standing closest to the checkout. The irony is that the most influential channel in the funnel can look like the least effective one in the dashboard.

What INCRMNTAL measures

Daily incremental conversions and incremental CPA for your OpenAI Ads spend. Cannibalization between ChatGPT Ads and your Search, Social and Retail Media budgets, so you know whether you added demand or moved it. Diminishing returns curves that show how far this channel scales before marginal CPA stops making sense. All always-on, no holdouts to babysit, no geo split to negotiate with your media team.

We already ran the numbers

INCRMNTAL published the first analysis of OpenAI Ads. Read what we found before you write your 2027 budget.