GA4 groups visits from AI assistants such as ChatGPT, Gemini, Deepseek, Copilot and Grok into its AI Assistant default channel. It excludes Google's AI Overviews and AI Mode, which stay in Organic Search. Open Reports, then Acquisition, then Traffic acquisition to see the channel, and build a custom channel group when an assistant you care about lands under Referral instead.
AI referral traffic means the visits that reach your site through a link in an AI assistant or an AI search answer, as your analytics records them. It counts only visits that pass a referrer or a tag, so it understates how often AI shows your business. Across the web the volume is growing fast, even if it still looks small in your own reports. AI platforms sent more than 1.13 billion referral visits to the world's top 1,000 websites in June 2025, up 357 percent from June 2024 (Similarweb, July 29, 2025).
- GA4's AI Assistant channel covers sources such as ChatGPT, Gemini, Deepseek, Copilot and Grok, and it leaves Google's AI Overviews and AI Mode in Organic Search.
- Google does not name Perplexity or Claude in that channel, so check where their visits land in your own property.
- GA4 can count only visits that arrive with a referrer or a tag, so the AI numbers you see are a floor.
Where does assistant traffic show up?
From the left menu, select Reports, and open Acquisition, Traffic acquisition (Traffic acquisition report). The report groups sessions by Session default channel group, and the AI Assistant row is the place to start. Change the dimension to Session source to see each assistant on its own row. The table below shows where each one usually lands.
| Assistant | Domain to look for | Default GA4 channel | What to check |
|---|---|---|---|
| ChatGPT | chatgpt.com | AI Assistant, since Google names ChatGPT | OpenAI adds utm_source=chatgpt.com to links from ChatGPT search results. |
| Gemini | gemini.google.com | AI Assistant, since Google names Gemini | Visits that arrive with no referrer at all land in Direct. |
| Microsoft Copilot | copilot.microsoft.com, and bing.com for some visits | AI Assistant for copilot.microsoft.com, Organic Search for bing.com | Neither Google nor Microsoft documents how to separate Copilot answers inside Bing from Bing search. |
| Deepseek and Grok | Their own domains | AI Assistant, since Google names both | Confirm the source names in your own Session source list. |
| Perplexity | perplexity.ai | Check your property. Google does not name Perplexity. | If it sits under Referral, add it to a custom channel group. |
| Claude | claude.ai | Check your property. Google does not name Claude. | If it sits under Referral, add it to a custom channel group. |
| Google AI Overviews and AI Mode | google.com | Organic Search | Google includes both in Organic Search. Use Search Console for their impressions. |
How do I see them all together?
Build one exploration rather than checking each source by hand. In GA4, open Explore and start a blank exploration. Add Session source as a dimension, and Sessions and Key events as metrics. Key events are what GA4 used to call conversions. Then add a filter where Session source matches regex.
Use this pattern as the filter value: .*(chatgpt|openai|perplexity|copilot|gemini|claude|deepseek|grok).*. The .* on each side matters. Google Analytics treats a regex as a full match by default, so the pattern without it matches only a source that is exactly the word chatgpt and never chatgpt.com (About regular expressions, Analytics Help). That gives you one row per assistant source and a total you can trend over months.
How do I build a custom AI channel group?
Google gives an example for AI assistants on its Custom channel groups page. Here is the same procedure with one safety check added.
- In Admin, under Data display, click Channel groups.
- Click Create new channel group, or use Copy to create new on the default group so you keep its other channels.
- Add a channel named AI assistants. Add a condition on the source and select matches regex.
- Enter a pattern that names whole assistant domains rather than words, such as ^(.*\.)?(chatgpt\.com|chat\.openai\.com|perplexity\.ai|gemini\.google\.com|copilot\.microsoft\.com|claude\.ai|you\.com|chat\.deepseek\.com|grok\.com)$, and add any other assistant domain your own Session source report shows. Keep the word pattern for the exploration above, since a word such as gemini can also match a site that is not an assistant.
- Click Reorder, drag AI assistants above Referral and click Apply. Google's example asks for the same order. Click Save group.
Test the pattern before you save it. Google's own example pattern starts with ^.*ai, which can also match sources you never meant to include, such as unrelated sites on a .ai domain. Leave Organic Search as it is, since clicks from AI Overviews cannot be separated from it. Google says custom channel groups apply to your reports retroactively, and a standard property can hold two of them besides the default group.
Why is the number so small?
There are three reasons, and only one of them is a measurement fault.
| Reason | Effect | Fixable? |
|---|---|---|
| The answer satisfied them | No visit at all | No. Analytics cannot count a visit that never happened. |
| They searched your name later | Shows as Direct or Organic Search | No. Attribution cannot see the earlier answer. |
| The referrer never arrived | Shows as Direct | Partly. Tag the links you control, and keep query strings through your redirects. |
Microsoft's Clarity documentation says that when the source is hidden, AI traffic might appear as Direct (Clarity AI channel group). One common way a source disappears is a privacy control I would never ask anyone to weaken. A page or an app that opens links with a no-referrer policy sends no Referer header at all (MDN, Referrer-Policy). GA4 then has nothing to read, and Google's rule files the session under Direct. So tag what you control and let the rest go.
We check this on our own site by setting GA4's referrers next to our own first party pixel. When the two disagree, that is where we start looking.
How do I see conversions from AI traffic?
Mark the actions that matter as key events. In Admin, under Data display, click Events, and turn on Mark as key event for each one (Create or modify key events). Read them in Traffic acquisition, where the AI Assistant row shows sessions and key events from the assistants GA4 recognizes. If checkout or booking runs on another domain, set up cross domain measurement. Google's path is Admin, Data collection and modification, Data streams, then your web stream, Configure tag settings and Configure your domains (Set up cross domain measurement). Google warns that self referrals can attribute traffic incorrectly. The numbers show what visitors from AI did on your site, not what AI influenced without a click.
How do I compare AI traffic with organic search?
In Traffic acquisition, keep Session default channel group as the dimension. Compare the AI Assistant and Organic Search rows for sessions, engaged sessions and key events over the same dates. Remember that clicks from Google's AI Overviews and AI Mode sit inside Organic Search, so you are comparing other assistants with all of Google search. Compare rates per session rather than totals, and look at the landing pages each channel reaches.
What should I actually watch?
Watch the trend rather than the absolute number. A small figure that grows month after month tells you more than any single month does, and I would read it quarterly before drawing a conclusion.
Adobe reported that in March 2026, AI referred visitors to US retail sites spent 48 percent more time on site and generated 37 percent more revenue per visit than other visitors (Adobe Digital Insights, April 2026). Your site is not Adobe's panel, so compare engaged sessions and key events for your own AI visitors, and read landing pages built for AI traffic for what to do with them.
Other tools, including Shopify's own analytics and our Shopify app's AI traffic tracking on the Pro plan, count referrals their own way. Do not expect their numbers to match GA4.
Common questions
Does GA4 have an AI channel built in?
It does. GA4 has an AI Assistant default channel for sources like ChatGPT, Gemini, Deepseek, Copilot and Grok, and that channel excludes Google's AI Overviews and AI Mode. Google documents the rule: GA4 sets the medium to ai-assistant and the campaign to (ai-assistant) when the referrer matches its list of AI assistants. Build the source based exploration as well, since it shows exactly which assistants you are counting. Source: Google Analytics Help, Default channel group, read September 26, 2026.
Which sources does the GA4 AI Assistant channel include?
Google describes the AI Assistant channel as covering sources like ChatGPT, Gemini, Deepseek, Copilot and Grok, and it excludes Google's AI Overviews and AI Mode. Google does not publish the full list of referrers behind it. So check your own property. Open Traffic acquisition, set the dimension to Session source, and look for perplexity.ai, claude.ai and other assistants under Referral. If they sit there, add them with a custom channel group placed above Referral, or filter them in an exploration.
Why does ChatGPT traffic show up as direct in GA4?
Some visits arrive without a referrer. OpenAI adds utm_source=chatgpt.com to links from ChatGPT search results, and GA4 reads that as the source. A visit loses that information when someone copies a link out of an answer, when an app opens it without a referrer, or when your own redirects drop the query string. GA4 files a session with no source under Direct. Check that your redirects keep utm parameters, and accept that part of AI traffic will always look direct.
What does utm_source=chatgpt.com mean in my analytics?
It means the visit came from a link in ChatGPT search. OpenAI says ChatGPT automatically adds utm_source=chatgpt.com to referral URLs, so analytics tools can record chatgpt.com as the source even when the browser passes no referrer. You did not add it, and you do not need to remove it. If your site redirects visitors, make sure the redirect keeps query parameters, or the source is lost. The parameter tells you the visit came from ChatGPT, not which question led there.
Why does ChatGPT traffic appear with different mediums in GA4?
GA4 builds source and medium from the referrer and any utm tags on the link, and its channel rules can then change the medium. Google documents that when the referrer matches its list of AI assistants, GA4 sets the medium to ai-assistant and the campaign to (ai-assistant). A link that carries only utm_source=chatgpt.com has no medium of its own, and older data may show referral. Check Session source / medium by date to see which rule applied, and group them all into one AI channel.
Can Google Analytics separate AI Overviews clicks from normal Google clicks?
It cannot. Google's own definition of the Organic Search channel includes AI Overviews and AI Mode, and its AI Assistant channel excludes them. So those clicks sit in Organic Search with every other Google click. Search Console counts them inside the Web search type of its Performance report, mixed in the same way. What Google does separate is impressions: the Generative AI performance report in Search Console shows how often your pages appeared in AI Overviews and AI Mode. Use that report beside GA4.
How do I track traffic from Perplexity?
Look for perplexity.ai as a session source. Google names ChatGPT, Gemini, Deepseek, Copilot and Grok as examples for its AI Assistant channel but does not name Perplexity, so in your property Perplexity visits may sit in AI Assistant or under Referral. Open Traffic acquisition, set the dimension to Session source and search for perplexity. If it appears under Referral, add it to a custom AI channel group. If you also use Microsoft Clarity, its AIPlatform channel lists Perplexity as a source.
Why do I see bing.com for Copilot?
Google lists Copilot among the sources of its AI Assistant channel, so visits from copilot.microsoft.com should land there. Visits with a bing.com referrer go to Organic Search, since Google's published list of search sites includes Bing. Some of them may come from Copilot answers shown inside Bing, and neither Google nor Microsoft documents how to tell them apart. Treat bing.com as mostly search. Microsoft Clarity counts only visits from copilot.microsoft.com and the other standalone assistant websites in its AI channel.
Sources
- Google, Default channel group, Analytics Help, and the list of default channel group sources it links. No update date is shown; read September 26, 2026.
- Google, Custom channel groups, Traffic acquisition report, About regular expressions, Create or modify key events, Set up cross domain measurement, Scopes of traffic source dimensions and URL builders, Analytics Help. No update dates are shown; read September 26, 2026.
- OpenAI, Publishers and Developers FAQ, OpenAI Help Center, shown as updated 28 days ago; read September 26, 2026.
- Microsoft, AIPlatform and PaidAIPlatform channel groups, Microsoft Clarity documentation, last updated September 23, 2025; read September 26, 2026.
- MDN, Referrer-Policy header, last modified September 4, 2026; read September 26, 2026.
- Google, What are impressions, position, and clicks?, Search Console Help; read September 26, 2026.
- Similarweb, AI referral traffic report of July 29, 2025, as recorded in our claim ledger (CLM-0104).
- Adobe Digital Insights, April 2026, as recorded in our claim ledger (CLM-0115).
Related reading
This guide is one part of how to measure AI visibility. Impressions from Google's AI features are in how to see AI Overviews and AI Mode performance in Search Console. For the business case, read Does AI Visibility Pay Off? The Business Case.
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