How to track AI traffic in GA4: ChatGPT, Perplexity, Gemini and more

More people now ask ChatGPT, Perplexity, Gemini or Claude for recommendations before they ever open Google. When those tools mention your business and someone clicks through, you want to know about it. The problem is that GA4 only sees part of that traffic, and most businesses do not know which part.

This guide shows how to track AI traffic in GA4 step by step: what the built-in AI Assistant channel counts, how to catch the visits it misses, and how to see which AI visitors actually become leads.

What GA4 counts, and what it misses

Before you set anything up, it helps to know the limits. No tracking setup sees all AI traffic, because some of it arrives with no information about where it came from.

Step 1: Check the built-in AI Assistant channel

In 2026, Google added an AI Assistant channel to GA4’s default channel group. Visits that GA4 recognizes as coming from AI assistants such as ChatGPT, Gemini, Copilot and others are given the medium ai-assistant and grouped into this channel automatically. Google has been rolling it out gradually, so check whether your property has it.

To find it:

1. Go to Reports → Acquisition → Traffic acquisition.
2. Make sure the table is grouped by Session default channel group.
3. Look for a row called AI Assistant.

If you see it, you already have a baseline. Keep it as it is: it is useful for comparing over time. But do not stop here, because the default channel misses some AI visits, as the next step shows.

Step 2: Find the AI visits the default channel misses

Some AI tools add a tag to their links. ChatGPT, for example, adds utm_source=chatgpt.com to many of the links it shows. When a visit carries a source like that but no medium, GA4 can file it as Unassigned or as chatgpt.com / (not set) instead of in the AI Assistant channel.

To see what is really arriving:

1. Go to Explore and start a Free form exploration.
2. Add the dimensions Session source / medium and Landing page + query string.
3. Add the metrics Sessions and Key events.
4. Add a filter where Session source contains chatgpt, perplexity, gemini, claude or copilot.

Save the exploration and check it once a month. If you see AI sessions sitting in Unassigned, Referral or (not set), build the custom channel group in step 3.

Step 3: Build a custom channel group for AI tools

A custom channel group lets you define your own “AI tools” channel that catches every AI source, whatever medium it arrives with.

1. Go to Admin (the cog icon, bottom left).
2. Under Data display, open Channel groups.
3. Click Create new channel group and name it, for example, “Channels with AI”.
4. Click Add new channel and name it “AI tools”.
5. Set the condition: Source · matches regex · and paste:

chatgpt\.com|chat\.openai\.com|openai|perplexity|claude\.ai|gemini\.google\.com|copilot\.microsoft\.com|deepseek|grok|meta\.ai

6. Save the channel. Then click Reorder and move AI tools to the top of the list. GA4 checks channels from top to bottom and stops at the first match, so if Referral or Unassigned sits above it, they will catch the AI visits first.
7. Click Save group.

Now, in Traffic acquisition, switch the table from “Session default channel group” to your new group. Allow a day or two for the data to show properly.

New AI tools appear regularly. Review the list in the regex every few months and add any new sources you see in your step 2 exploration.

Step 4: Track what AI visitors do

Traffic numbers on their own do not tell you much. What matters is whether AI visitors become leads and customers.

• Make sure your key events are set up: form submissions, phone clicks, bookings and purchases, marked as key events in GA4.
• Compare channels on key events, not sessions. In Traffic acquisition, look at key events and the key event rate for AI tools next to Organic Search and Paid Search. AI visitors are often few but well informed, because the AI already explained what you do.
• Look at landing pages. Which pages do AI tools send people to? Those pages are being quoted. Make sure they have a clear next step.

Step 5: Capture the AI traffic GA4 cannot see

Some AI-driven visits will never show up as AI in GA4: people who use an AI app that strips the source, or who read about you in an AI answer and then type your name into Google. You can still capture part of this:

• Ask on your forms. Add a “How did you hear about us?” field with “ChatGPT or another AI tool” as an option. It is low-tech and surprisingly revealing.
• Pass the source to your CRM. Capture the source and medium on the first page view and send them with every form submission, so each lead in your CRM shows where it came from.
• Watch branded searches. A rise in people searching your business name, with no change in your ads or PR, can be a sign that AI tools are mentioning you.
• Remember Google’s own AI answers. Clicks from AI Overviews and AI Mode are counted as Organic Search, not as AI. Search Console is the place to watch how your pages appear in Google search overall.

This is the same principle as all good tracking: follow each lead from first touch to sale. We cover the business side of that in our guide to customer acquisition cost.

How to get more AI traffic in the first place

Tracking shows you where you stand. Getting recommended more often comes down to being the clearest, most trusted answer: specific pages that answer real questions, consistent business details everywhere, and reviews and mentions on other sites. We cover the steps in how to get your business recommended by ChatGPT. That is also what our AI search optimization work focuses on, built on solid SEO. It is also one part of the bigger picture in our guide on how to get and keep customers.

Questions about tracking AI traffic

Can GA4 track ChatGPT traffic?

Partly. Clicks from ChatGPT in a browser usually arrive with a source GA4 can recognize, either through the AI Assistant channel or as chatgpt.com in your source data. Visits from the ChatGPT app and from people who copy a link often arrive with no source and are counted as Direct.

Why does my AI traffic show as Direct?

Because the visit arrived without any information about where it came from. Many apps and desktop clients do not pass that information on. GA4 counts any visit with no known source as Direct.

Are Google AI Overviews counted as AI traffic?

No. Clicks from AI Overviews and AI Mode are counted as Organic Search in GA4. They are not separated from regular search clicks.

Does a custom channel group change my past data?

Custom channel groups are applied when you view reports, so they generally work on past data as well as new data. Keep the default channel group too, so you always have an unchanged view to compare against.

How much traffic should I expect from AI tools?

For most businesses it is still a small share of total visits, but it is growing and often converts well because people arrive already informed. Watch the trend and the leads it brings, not just the size.

Want your tracking set up properly, from first click to customer? See our tracking and analytics service or contact us.