The Guide to Tracking LLM Traffic in Google Analytics 4

Why this is the most-requested analytics setup of 2026

Marketers ask for one specific GA4 setup more than any other right now: how to see which traffic comes from ChatGPT, Gemini, and other AI tools. The native GA4 channel groupings don't separate AI referrals from generic ones, so AI traffic gets buried in the "Referral" bucket where it's impossible to analyze. Fixing this is straightforward, but it requires a few configuration steps that aren't obvious.

Method 1: Quick filter (for one-off analysis)

If you just want to see AI traffic in a specific report:

1. Open GA4, navigate to Reports → Acquisition → Traffic acquisition.
2. Click the "+" next to filters, choose "Session source/medium" as the dimension.
3. Set match type to "matches regex (partial)".
4. Paste this regex: openai|chatgpt|copilot|gemini|gpt|perplexity|writesonic|bard|claude|anthropic|grok

The report now shows only sessions originating from AI tools. You can see sessions, engagement duration, key events, and conversions for AI traffic specifically.

Method 2: Custom channel group (for ongoing reporting)

For permanent tracking, build the AI channel into your GA4 channel group so every report breaks it out automatically:

1. In GA4 admin settings, navigate to Data display → Channel groups.
2. Create a new custom channel group (or edit your default one if you're comfortable changing standard report behavior).
3. Add a new channel: name it "AI Referral".
4. Set the condition: Source/medium contains regex matching the same pattern above.
5. Drag the new "AI Referral" channel above "Referral" in the priority list. Channel rules are evaluated in order, AI traffic must be matched before the generic referral rule catches it.

Save and apply. From that point on, every report using Default Channel Group (or your custom group) will show AI Referral as its own row.

Method 3: Looker Studio dashboard

If you want a permanent dashboard for stakeholders:

1. Connect GA4 as a data source in Looker Studio.
2. Create a new chart filtered to your AI Referral channel.
3. Add metrics: sessions, engaged sessions, conversions, conversion rate, engagement time per session.
4. Add a date range control so users can see week-over-week changes.

This is the simplest way to give your CMO an at-a-glance view of how AI traffic is trending.

The regex you need to maintain

The pattern above covers the major AI platforms today, but new tools launch every quarter. Plan to update the regex every 3-6 months. As of early 2026, common additions include "you.com", "phind", "neeva", "kagi", and various enterprise AI tools that start to send measurable traffic.

The hard truth about GA4 and AI traffic

GA4 captures what happens after the click. It can't tell you what the AI said before the user clicked. You won't know which prompts drove the visit, whether your brand was framed positively, or which competitors were mentioned in the same answer. For that level of insight, GA4 needs to be combined with prompt-level AI visibility tracking. But for basic attribution and trend analysis, the GA4 setup above is the foundation everyone should have running by the end of this quarter.

For the broader measurement framework this feeds into: How to Measure AI Visibility: A Practical Framework with Real Metrics.