How to Track ChatGPT and AI Traffic in GA4 (2027)

To track AI traffic in GA4, start with the AI Assistant row in Reports > Acquisition > Traffic acquisition. Then add your own regex filter or channel group, because Google does not publish the full list of assistants behind that row.

This guide covers where each assistant's visits land, a regex to paste and the channel group setup. It also covers the share you cannot see by source. It ends with what server logs add and what they do not.

What is AI referral traffic, or LLM traffic?#

AI referral traffic is a visit that starts when someone clicks a link inside an AI assistant's answer. People also call it LLM traffic, after the large language models behind ChatGPT, Claude or Gemini. In GA4 it is an ordinary session with the assistant's domain as its source.

Two other things are often counted under the same name, and they belong somewhere else:

• Clicks from Google's AI Overviews and AI Mode. GA4 puts them in Organic Search, together with normal Google results.
• Requests from AI crawlers and fetchers such as GPTBot or ChatGPT-User. These are software reading your page, not people visiting it, and they show up in server logs rather than in GA4.

Keeping the three apart matters. A rise in crawler hits says nothing about visitors, and AI Overview clicks are already inside your search numbers.

Where do ChatGPT, Perplexity, Gemini and Claude visits show up in GA4?#

They show up under the assistant's hostname as Session source, provided the browser passes a referrer or the link carries a UTM tag. The table lists the hostnames as they resolved on November 11, 2026, and what the vendors themselves document.

Two details explain the table. First, copilot.microsoft.com redirected to copilot.com on November 11, 2026, so a regex needs both. Second, the chatgpt.com server sends the strict-origin-when-cross-origin referrer policy. MDN's Referrer-Policy reference says that policy passes only the origin to other HTTPS sites. You see chatgpt.com, never the conversation.

Does ChatGPT add utm_source=chatgpt.com to links?

Yes, according to OpenAI. Its Publishers and Developers FAQ says ChatGPT automatically includes utm_source=chatgpt.com in referral URLs. It ties this to sites that allow OAI-SearchBot and names Google Analytics as a way to track the traffic.

The tag is not a guarantee on every click. On October 14, 2026, Search Engine Roundtable reported that ChatGPT links had briefly lost the tag and the referrer. Those visits landed as Direct. The observers quoted there called it a bug a day later. That report is third-party; OpenAI made no statement in it.

Why does ChatGPT traffic show as Direct in GA4?#

Because the visit arrives without a referrer and without a UTM tag, and GA4 then has nothing to attribute. Google's page on (direct) / (none) traffic lists the general causes. They include missing UTM parameters, redirects or shorteners that strip them, typed URLs, offline documents and ad blockers.

AI assistants add their own versions of those causes:

• Copy and paste. A reader copies a URL from an answer into the address bar. To GA4 that is a typed visit.
• Apps. Desktop and mobile apps can open links in a way that passes no referrer. No vendor in the table documents its app behaviour, so treat this as a likely cause, not a measured one.
• Links without a tag. If a link has no UTM and the referrer is withheld, the visit is Direct, as in the October 2026 incident above.
• Consent and blocking. If the visitor declines tracking or blocks the tag, there may be no session at all.

There is no way to recover these visits by source. What you can do is watch landing pages. A rise in Direct sessions on deep pages nobody types by hand, at the same time as AI referrals grow, is a reasonable hint. It is not proof.

How do I see AI traffic in GA4 in two minutes?#

Use the AI Assistant row first, then a regex filter for the rest. Both work in the standard Traffic acquisition report, with no admin rights needed.

1. In the left menu, select Reports, then Acquisition > Traffic acquisition.
2. Read the AI Assistant row; the report opens grouped by default channel. Google's default channel group page says GA4 sets the medium to ai-assistant when the referrer matches its list of AI assistants.
3. Change the primary dimension to Session source / medium. Type ai-assistant into the search box above the table to list those sources.
4. For assistants outside Google's list, click Add filter, choose Session source, set the match type to matches regex, and paste the regex below.

Google's report filter documentation lists four regex match types and says report regex is case sensitive and limited to 250 characters. Its regex page adds that GA4 uses full match by default, which is why the pattern starts and ends with .*.

Ready-to-copy regex for AI assistants

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

The pattern is 137 characters, well under the 250 limit, and uses only plain alternation. It names whole hostnames, so a source like gmail.com or an unrelated .ai domain stays out. Add a hostname when a new assistant starts sending visits, and check the result against the Session source list.

Google's own example regex in its custom channel group help is broader. Its first branch, ^.*ai, matches every source ending in "ai", and .*gpt.* matches any source containing "gpt". Test any pattern against your real source list before you trust the totals.

How do I build an "AI assistants" channel group in GA4?#

Copy the default channel group, add an AI assistants channel with the regex, and move it above Referral. Google documents the exact steps on its custom channel groups page, including an AI assistants example.

1. In Admin, under Data display, click Channel groups. You need the Editor role or above on the property.
2. Click Create new channel group. GA4 starts with a copy of the default group. Name it, for example "Channels with AI".
3. Click Add new channel and name it "AI assistants".
4. Click Add condition group, choose Source, select matches regex and paste the regex above. Click Save channel.
5. Click Reorder and drag AI assistants above Referral. Click Apply, then Save group.

The order matters. Google says traffic goes into "the first channel whose definition it matches." Placed below Referral, the new channel would stay empty for every assistant that arrives as a referral. Google also suggests placing it above Organic Search if needed.

Limits and behaviour to know

Afterwards, open Traffic acquisition and pick your new group as the primary dimension. You can also make it the property's primary channel group from the Channel groups page. Google says that switch only fills data from that point forward.

How do I compare engagement and conversions of AI visits?#

Put AI visits next to your other channels in Traffic acquisition and compare rates, not totals. The report already holds the metrics you need, as Google's Traffic acquisition reference lists them.

A key event only counts once you mark it. Google's key events page allows up to 30 on a standard property. Mark sign-ups, purchases or contact form sends before you compare.

For a deeper look, open Explore and start a Free form exploration. Add Session source as a row, the four metrics as values, and a filter on Session source with the regex. Add Landing page as a second row to see which pages assistants send people to. Keep the date range long, because small AI samples swing a lot from week to week.

Are Google AI Overviews and AI Mode clicks counted as AI traffic?#

No. In GA4, Google's default channel page says the AI Assistant channel "excludes Google's AI Overviews and AI Mode," and Organic Search includes them. In Search Console they sit inside the normal search data.

Google's page on AI features and your website says this traffic counts as overall search traffic. It appears in the Performance report under the Web search type. Its Performance report counting rules add the detail:

• A click on an external link in an AI Overview or in AI Mode counts as a click.
• An AI Overview takes a single position, and every link inside it gets that position.
• A follow-up question in AI Mode counts as a new query.

Google gives no filter that separates these clicks from classic results. Gemini at gemini.google.com is different: it is a separate assistant, and GA4 lists it under AI Assistant.

What do server logs show about AI bots?#

Logs show AI crawlers and fetchers requesting your pages, which GA4 never shows. Those requests are not visits. Each vendor documents its user agents and what they do:

Sources: OpenAI's crawler overview, Perplexity's crawler guide and Anthropic's ClaudeBot article. OpenAI and Perplexity also publish IP lists, so you can check that a request claiming to be their bot really comes from them.

To count these requests on a standard access log, search for the user agent names:

grep -E "GPTBot|OAI-SearchBot|ChatGPT-User|PerplexityBot|Perplexity-User|ClaudeBot|Claude-User|Claude-SearchBot" access.log | wc -l

A rising ChatGPT-User count can mean your page is being read during conversations. It does not mean anyone clicked through. GA4 also excludes known bots automatically, as our article on what GA4 bot filtering excludes explains. For the wider picture of crawlers and bad bots, see our bot traffic explainer.

How can I test that my AI channel works?#

Send a few visits you know about and check where they land. The quickest test is your own click: ask an assistant about your page, click its link, and watch Reports > Realtime for the source.

For a repeatable test, create links with your own UTM values and open them, following our guide to UTM tracking in GA4. Your manual UTM source and medium decide the channel, so set them to match the rule you want to test. Traffic Creator campaigns can also send visits with an AI assistant as referrer source, as our overview of website traffic sources lists. That is useful when you want to see a new channel group fill with a known count.

If test visits do not appear at all, work through why traffic may not appear in GA4. For the basic reports this guide builds on, start with how to check website traffic.

Frequently asked questions#