How to measure whether ChatGPT ads really sell

The most common advertising mistake is spending money without tracking. You see people clicking, but you don't know whether they buy. It's like running a shop where you know how many people walked in but not how much you sold. With ChatGPT ads this matters twice as much, because they're new and every decision should be based on numbers.

What we actually want to measure

Every business has its own "win". In marketing it's called a conversion. It can be:

• a purchase in an online store,
• a completed form or a quote request,
• a phone call or a booking,
• a sign-up for a webinar or course.

First decide what your win is. Only then set up tracking.

Two ways to track

Code on your website (pixel)

A pixel is a small snippet of code you add to your website. When someone comes from an ad and buys, the code records it and sends the information to the ad platform. Setup is quick; your web admin can often handle it.

The downside: some browsers and ad blockers stop this code, so you won't see some purchases.

Server-side tracking

Here, your website or store itself sends the purchase data to the ad platform, not the visitor's browser. For ChatGPT this is called the Conversions API. It's more reliable, but setup needs a developer or an integration via your e-commerce platform.

It's best to use both. The platform matches the data and won't count a purchase twice.

Don't forget consent (GDPR)

In the EU, visitors must consent to tracking. That's the cookie banner you know from every website. The ad tracking code therefore:

• must be listed in the cookie banner,
• may only run after the visitor consents.

So you'll never see absolutely every purchase. That's fine. What matters is that the numbers are accurate enough to make decisions.

Connect it with Google Analytics

Most businesses use Google Analytics to track traffic. To see visitors from ChatGPT ads there too, add UTM tags to your ad links. They're short suffixes after the page address, for example ?utm_source=chatgpt&utm_medium=ads. Google Analytics then knows exactly where the visitor came from.

Which numbers to watch

Four are enough:

1. How much you spent.
2. How many purchases or leads you got.
3. What one customer costs: money spent divided by the number of purchases.
4. How much you earned for every euro invested. If you put €100 into ads and sell €500 worth, every euro brought you €5 in revenue.

Other numbers (how many people saw the ad, how many clicked) help you fine-tune the ads, but these four decide your profit.

Pre-launch checklist

• I know what my "win" is (purchase, form, call).
• The tracking code is on the website and runs after cookie consent.
• Ideally, server-side tracking is set up too.
• Ad links have UTM tags.
• I've made a test purchase and checked that it was recorded.

Summary

Tracking is the insurance that turns advertising into an investment instead of a gamble. Set it up before you spend your first euro, and above all watch what one customer costs. If you're not sure how, we'll set up tracking as part of your ChatGPT ads.