How to track AI traffic in GA4: a channel for ChatGPT and others

By default, GA4 files a visit from ChatGPT under Referral, next to a link from a partner's blog, and a visit from Gemini somewhere similar. Nobody looks there. A custom channel puts every assistant's visits in one line you can watch, and takes about ten minutes.

Before you start

You need the Editor role (or above) on the GA4 property. A standard property can have two custom channel groups besides the default one, and each group up to 50 channels, so check whether someone has already used the slots.

Step 1: create a custom channel group

1. In GA4, go to Admin, then Data display, then Channel groups.
2. Click Create new channel group. GA4 starts you from a copy of the default group, which is what you want: every existing channel stays, and you add one.
3. Name it something like "Default + AI assistants".

Step 2: add an AI assistants channel

1. Click Add new channel and name it AI assistants.
2. Click Add condition group, choose the dimension Source, and the match type matches regex.
3. Paste a regular expression covering the assistants' domains. One that covers the main ones as of November 2026:

.*(chatgpt|openai|perplexity|gemini\.google|copilot\.microsoft|claude\.ai|deepseek|meta\.ai).*

4. Click Save channel.

The leading and trailing .* make the pattern match a domain anywhere in the source value. Google's own help page includes an AI assistants example in the same spirit and notes you'll need to update it as assistants and their addresses change.

Step 3: put it above Referral

GA4 assigns each session to the first channel whose rules match, in order. Click Reorder, drag AI assistants above Referral, click Apply, then Save group. If you skip this, the visits stay in Referral.

Step 4: read it

In Reports, open Acquisition, then Traffic acquisition, and switch the dimension selector to your new channel group. Custom channel groups apply to past data as well, so you'll see history, not just visits from today.

Look at more than sessions: engaged sessions, conversions and the landing pages. AI referrals often land deep in a site, on a specific product or help page, rather than the homepage, which tells you which pages the assistants cite.

Also tag what you can

Many links ChatGPT shows carry utm_source=chatgpt.com, which GA4 reads as the source, so those visits land in your channel even when the referrer is stripped. Some apps and desktop clients send no referrer at all, and those visits arrive as Direct. There's nothing to do about that except know it.

What GA4 can't see

AI Overviews and AI Mode. Clicks from Google's AI features arrive as ordinary Google organic traffic. Google says sites appearing in AI Overviews and AI Mode are "included in the overall search traffic" in Search Console's Performance report, under the Web search type. Since August 2026 every site also has Search Console's generative AI report, which shows impressions from these features by page, but not clicks or queries.

The answers nobody clicked. This is the big one. Pew Research Center found that people who saw an AI summary on Google went on to click an ordinary result in 8% of visits, and in 15% when no summary appeared. Assistants often answer the whole question, so a brand can be named in thousands of answers and receive a few dozen visits. Referral traffic is a floor, not a measure of AI visibility.

How to use the number

• Watch the trend, not the level. A month-on-month rise in AI referrals, on the landing pages you worked on, is a good sign.
• Read it beside visibility. Our guide to measuring AI visibility covers counting answers that name and cite you. Traffic and visibility moving together is a stronger story than either alone.
• Check the landing pages (for shops, product pages usually lead; see AEO for ecommerce). If one page gets most of the AI traffic, it's the page assistants cite. Keep it current.
• Don't report it as reach. A report that says "AI sent 140 visits" undersells work that got you named in most buying answers.

For how ChatGPT decides which pages to link in the first place, see how ChatGPT search picks sources. For what Google's two AI features count where, see AI Overviews vs AI Mode.