How do I see ChatGPT and Perplexity traffic in Google Analytics 4?

Since 13 May 2026, GA4 puts visits from recognised AI assistants into a separate AI Assistant channel. Open Reports, then Acquisition → Traffic acquisition: the table is grouped by the session's default channel group, and AI Assistant appears as its own row once such visits arrive.

Google's rule works on the referrer, the address of the page a visitor came from. When the referrer matches Google's list of AI assistants, GA4 sets the medium to ai-assistant and the campaign to (ai-assistant). Google's help pages name ChatGPT, Gemini, Claude, DeepSeek, Copilot and Grok as examples and do not publish the full list.

Google's announcement does not say whether visits before 13 May 2026 were moved into the new channel, so check a date range after that day.

The AI Assistant channel misses visits that reach your site without a recognised referrer, so tagged ChatGPT links, visits from apps and Perplexity can sit in other channels. GA4 assigns the channel from the referrer alone.

Three default rules decide where those visits go instead. A visit with no referrer and no tags counts as Direct. A link from a site that Google does not treat as an assistant stays in Referral. Google warns that missing UTM parameters produce (not set) values, and a session whose source / medium is reported as (not set) is shown as Unassigned.

Perplexity is the clearest gap. Google's examples for the channel do not include it, while Microsoft Clarity lists Perplexity among the AI sources it recognises. Check where perplexity.ai sits in your own report instead of assuming either way.

ChatGPT adds utm_source=chatgpt.com to the links in its answers, so the visit stays identifiable even when no referrer arrives. OpenAI states this in its Publishers and Developers FAQ and documents only that one parameter. A UTM tag is a label inside the link itself; a referrer is information the browser sends separately and may withhold.

On our site, in the week of 30 September–7 October 2026, almost one in five visitors counted by Vercel Web Analytics arrived with utm_source=chatgpt.com. Vercel showed them in its UTM Parameters panel, which is part of the Web Analytics Plus and Enterprise plans.

Vercel's documentation explains why the referrer report can tell a different story: a referrer is recorded only as the Referrer-Policy header allows and only when the link has no rel="noreferrer" attribute. The UTM panel simply shows the tags the address carried. A report built only on referrers can therefore undercount ChatGPT in any analytics tool.

Build a custom channel group with one AI channel that matches on source alone and, as Google's help advises, sits above Referral. In Admin, under Data display, open Channel groups and choose Create new channel group; GA4 starts it as a copy of the default group.

Matching on source matters because OpenAI documents only a source in the ChatGPT tag, so a rule that also requires a medium can miss those visits. A standard GA4 property allows two custom channel groups with up to 50 channels each, and Google applies them to past reports, so the new channel also covers earlier months.

GA4 reads a regular expression as a full, case-sensitive match, so the pattern needs .* at both ends to allow anything around the name. One condition is enough: set Source to matches regex and paste this single line: .*(chatgpt|openai|perplexity|claude|gemini|copilot|deepseek|grok).*

Do not copy Google's own example unchanged. Its pattern begins with ^.*ai| and, under full matching, that part may also match any source ending in “ai”, such as any website on a .ai domain, so ordinary referrals could be counted as assistants.

GA4 counts only visitors whose browser loads its script, so on get-geo.ai in the week of 30 September–7 October 2026 it reported a little over a third of the visitors recorded by Vercel Web Analytics. Vercel identifies visitors by a hash of the request and uses no third-party cookies, and on our site it runs without a consent banner.

Three causes stack up, and we have not measured their shares. Our consent banner appears for visitors from the EU, the EEA, the UK and Switzerland, and GA4 and Microsoft Clarity load for them only after they agree. Ad and tracking blockers stop some scripts. The tools also define a visitor differently: Vercel keeps a visitor session for no more than 24 hours, while GA4 reports users.

Microsoft Clarity runs only on our English pages and counts sessions, so we do not compare its total with GA4. Clarity has its own AI channel, AIPlatform, assigned from known referral patterns. Read AI visits in GA4 as a lower bound and compare weeks within one tool, not totals across tools.

GA4 counts clicks from Google's AI Overviews and AI Mode as Organic Search, so they never reach the AI Assistant channel. Google's definition of the Organic Search channel names both surfaces explicitly.

Search Console shows the other half. Its Generative AI performance report lists impressions of your links in AI Overviews and AI Mode by page, country, device and date, without clicks or queries, and does not separate the two surfaces. Impressions are not visits. Our guide to Google AI Overviews explains how pages get there.

The Gemini app is a different case: Gemini is one of Google's named examples for the AI Assistant channel.

An AI traffic report should name the sources it counted, include tagged ChatGPT visits, state how much of the audience analytics can see, and sit next to measurements of the answers themselves. Four items make the number checkable: the sources and channels counted, whether utm_source=chatgpt.com visits outside the AI Assistant channel are included, the consent and blocker limits, and citation measurements for the same period.

Referral traffic is the lagging signal. Citation rate, the share of repeated test answers that cite your site, and share of voice, your share of brand mentions against competitors in the same answers, describe the answers directly; our guide to measuring AI visibility and our measurement method explain both. Our checklist for judging whether GEO is working puts traffic alongside the other signals.

If you want to see the answers behind the traffic, our free AI visibility audit covers ten prompts in one language where you are invisible, the current answers, crawler-access checks and specific fixes, in writing.

Ten checks cover where AI visits sit in GA4, what the AI Assistant channel misses and how to read the totals. Run them once after setting up the channel, then with each monthly report.