How to Track ChatGPT and AI Assistant Traffic in GA4

Most businesses already get some visits from ChatGPT, Perplexity, Gemini and Copilot. Very few can see them, because Google Analytics 4 mixes them in with every other referring website.

This guide shows you how to track AI traffic in GA4 with a custom channel that takes about ten minutes to set up, a ready regex you can paste in, an exploration report for deeper analysis and the limits you need to understand before you report the numbers. It supports the measurement step in our complete AI SEO guide.

Where AI traffic shows up in GA4 by default

When someone clicks a link inside an AI answer, their browser usually passes the assistant's domain as the referrer. GA4 records that domain as the session source and, by default, puts the visit in the Referral channel alongside every other website that links to you.

These are the source values you are most likely to see:

ChatGPT also adds utm_source=chatgpt.com to many of the links it shows. Those visits can appear with a source of chatgpt.com and a medium of (none) or (not set) rather than referral, which is why the setup below matches on source only.

Step 1: Check your current AI referrals in two minutes

Before building anything, see what is already there.

1. Open Reports, then Acquisition, then Traffic acquisition.
2. Change the primary dimension to Session source / medium.
3. Set the date range to the last three to six months.
4. Type chatgpt in the search box above the table, then repeat for perplexity, gemini, copilot and claude.

If any rows appear, you already have AI traffic worth tracking. Note any AI sources not on the list above; you will add them to the regex.

Step 2: Create an AI Assistants channel group

A custom channel group gives AI visits their own line in every acquisition report.

1. 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, so all your existing channels stay in place.
3. Name the group, for example "Channels with AI".
4. Click Add new channel and name it AI Assistants.
5. Add a condition: Session source, matches regex, and paste the regex below.
6. Save the channel.
7. Click Reorder and drag AI Assistants above Referral. This step matters. GA4 assigns each visit to the first channel whose rules it matches, so if Referral sits above your new channel, AI visits stay in Referral.
8. Click Apply, then Save group.

Here is the regex:

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

The .* at each end lets the pattern match subdomains such as www.perplexity.ai. If Step 1 showed other AI sources, add them inside the brackets, separated by a | character, with a backslash before each dot.

Custom channel groups can be applied to historical data, so once the group is saved you can select it in your Traffic acquisition report and compare past months straight away.

Step 3: Build an exploration for deeper analysis

The channel tells you how many AI visits you get. An exploration tells you where they land and what they do.

1. Go to Explore and create a Free form exploration.
2. Add dimensions: Session source, Landing page + query string and Device category.
3. Add metrics: Sessions, Engaged sessions, Engagement rate, Average engagement time per session and Key events.
4. Add a filter: Session source matches regex, using the same pattern as above.
5. Put Session source and Landing page in rows, and the metrics in values.

You will quickly see which pages AI assistants send people to. Those pages are the ones assistants already trust, so they are worth improving and linking from. Our guide on how to write content AI assistants quote explains how to strengthen them.

Step 4: Count the conversions that matter

Traffic alone does not prove value. Make sure GA4 records the actions that lead to revenue as key events:

• Contact and quote form submissions
• Clicks on phone numbers and WhatsApp buttons
• Purchases, add to cart and checkout steps for online stores
• Brochure or price list downloads

Then compare the key event rate of the AI Assistants channel with organic search and paid channels. In our experience AI visitors often arrive further along in their decision, because the assistant has already explained who you are, so conversion rate is a better measure than volume.

If tracking is not set up properly yet, fix that first. Part 8 of our SEO audit checklist covers the basics.

The AI traffic GA4 cannot see

Your AI channel will undercount. Know the gaps before you report the number.

That last row is important. A lot of AI influence never produces a referral visit. A buyer sees your name in ChatGPT, then searches your brand on Google or messages you on WhatsApp. This is why analytics should be paired with direct checks of what assistants say. Our guide on how to check if ChatGPT recommends your brand shows how to run them.

For Google's own AI features, read our breakdown of Google AI Overviews and what they mean for your traffic.

What to report every month

Keep the report short and consistent:

Compare each month with the same month before the work began, and add a short note on what changed on the site.

What it looks like on a real account

For a drone light show company, AI assistants sent no measurable visits before our work began. After six months of keyword research by occasion and city, rewritten service pages, structured data, event content and more than 45 quality backlinks, the AI channel recorded 23 visitors in one month, alongside a 320% rise in organic traffic. Without a separate channel, those visits would have disappeared into Referral. See the drone light show SEO case study.

Want it set up for you?

We set up AI traffic tracking as part of every engagement, along with monthly AI visibility checks. Request a free SEO and AI visibility audit and we will show you how much AI traffic you already get and where it lands. You can also explore our AI SEO services.