Measurement Gaps Are Keeping Brands' ChatGPT Ad Budgets Stuck at 'Test' Level
Updated: 6 days ago
TL;DR: Advertisers are keeping ChatGPT ad budgets tiny because OpenAI's conversion tracking is slow, patchy and short on demographic data, leaving brands unwilling to scale beyond test spend.
The budgets that will not grow
OpenAI has been steadily building out advertising formats inside ChatGPT, but the money is not following. According to a Digiday report on 1 October, measurement gaps are capping brand investment at test levels, with advertisers unwilling to scale until they can trust the numbers.
The scale of the gap is stark. One executive described clients spending roughly $10 million a month on Google while committing under $100,000 a month to ChatGPT. That is not a vote of no confidence in the audience — it is a vote of no confidence in the reporting.
Why advertisers are hesitant
The specific complaints are practical, not philosophical. Agency Accuracast found zero recorded conversions two weeks after form fills that clearly happened, and detected only around 20 of roughly 100 clicks independently. When a platform cannot reliably count what it delivered, optimisation becomes guesswork.
Timing compounds the problem. Conversion data from ChatGPT reportedly arrives 24 to 36 hours late, versus within hours on Google, and comes without the demographic or prompt-level detail buyers rely on to target and refine. Jellyfish's Victor Batista noted that teams are optimising to cost-per-acquisition and that confidence improves as more data accumulates — but the data has to arrive first.
There is also a trust dimension. Many brands are declining to enable conversion tracking at all over concerns about how OpenAI handles their data, which starves the system of the very signals it needs to prove its worth.
Inventory is not the bottleneck
Here is Marketing Minute's read. OpenAI's ad business is maturing on formats and reach, but the gating factor is trust and measurement, not inventory. The audience is there and the placements work; what is missing is the reliable feedback loop that lets a performance marketer justify the next dollar.
This is the familiar adolescence of every new ad channel. Early search, early social and early retail media all went through a phase where spend outran the ability to measure it. The platforms that won were the ones that closed the measurement gap fastest — and the advertisers who won were the ones who tested cheaply while they waited.
How to play it now
The sensible posture is to treat ChatGPT ads as a learning line item, funded from an experimental budget rather than carved out of proven performance channels. Demand third-party verification of conversions before scaling, and set a clear threshold — a level of measurement reliability — that must be met before more money moves.
In short: test emerging ad platforms with money you can afford to lose, and keep your real performance budget where you can still prove the sales are real. The upside of being early is real, but only if you can survive being wrong cheaply.
Quick FAQ
Why are brands not spending more on ChatGPT ads?
Advertisers say OpenAI's conversion tracking is slow, incomplete and lacks demographic detail, so they cannot reliably prove results — keeping budgets at test level. One exec cited clients spending $10m a month on Google but under $100k on ChatGPT.
What are the main measurement problems with ChatGPT advertising?
Reported issues include missed conversions, data arriving 24 to 36 hours late versus hours on Google, no prompt-level or demographic detail, and some brands declining to enable tracking over data-handling concerns.
Should businesses advertise on ChatGPT yet?
Treat it as a test channel funded from experimental budget, demand independent verification of conversions, and avoid shifting core performance spend until the measurement is reliable.
Every new ad platform asks you to spend before it can prove the spend worked. The discipline is to treat that gap honestly: fund it from your experimental budget, demand independent verification, and refuse to move real performance money until the conversion data is reliable. Measurement, not inventory, is what unlocks scale. — Daniel Nikolla, Founder of Merx Marketing
Test emerging ad platforms with money you can afford to lose — never shift real performance budget until you can independently prove the sales are real.
How would you verify that a new ad platform's reported conversions are actually driving revenue before you scale?
If you would like to know more about this topic, please contact us on danieln@merxmarketing.co.uk
Sources: Digiday.
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Written by Daniel Nikolla, Founder of Merx Marketing Ltd and Marketing Minute
