TL;DR
Google shipped two separate AI-traffic features this spring, and reading your numbers correctly means knowing which is which. The May 13, 2026 AI Assistant channel groups sessions whose medium is ai-assistant, with a source list of ChatGPT, Gemini, Deepseek, Copilot, and Grok [2]. The June 11, 2026 Source Group dimension consolidates messy source strings into one canonical value per platform, names ChatGPT (OpenAI) and Perplexity in Google's announcement, and populates retroactively across your historical data [1]. Notice what falls through: Perplexity is not in the AI Assistant channel's live definition, and some AI-browser traffic arrives with the referrer stripped and lands in Direct where no grouping can reach it [3]. On our own store, AI assistant sessions are already a measurable channel row with revenue attached.
Key Takeaways
- Two features, two dates: the AI Assistant channel (May 13, 2026, keyed on medium
ai-assistant) and the Source Group dimension (June 11, 2026, retroactive) [1] [2]. - The AI Assistant channel's live definition covers ChatGPT, Gemini, Deepseek, Copilot, and Grok, and explicitly excludes Google's AI Overviews and AI Mode. Perplexity is not in the list; its visits stay in Referral [2].
- Source Group is the layer that names Perplexity. Google's announcement lists "ChatGPT (OpenAI) and Perplexity" as built-in groupings [1].
- As of mid-July 2026, the dimension appears as "Source grouping" in the Advertising workspace's Conversion performance report; the standard Traffic acquisition dimension picker does not offer it. We verified this in a live property on July 17, 2026.
- Traffic from AI browsers and in-app webviews often arrives with no referrer and reports as Direct; no grouping feature can recover it [3].
- The same June 11 release added a hostname data filter, which excludes events from unapproved hostnames like staging domains [1].
- In our own install-attribution survey, "AI Assistant" is the top answer for how merchants found our app: 18 of 46 responses (39.1%), ahead of Google at 32.6%. Multi-select, so shares exceed 100% (app-install attribution, not store traffic).
What did Google ship on June 11, 2026?
Two things, per the What's New entry: the Source Group dimension and a hostname data filter [1].
Source Group tackles a problem every store with real traffic knows: the same platform shows up under a half-dozen source strings. Google's own example is Instagram traffic arriving as %instagram% variants and ig, now consolidated into a single "Instagram" value. The part that made this release news outside the analytics bubble is Google's sentence about emerging sources: the dimension includes "built-in grouping for emerging traffic sources like ChatGPT (OpenAI) and Perplexity" [1]. Google publishes no complete mapping list of which raw sources fold into which group, so treat any specific domain-to-group table you see in the wild as practitioner-observed rather than official.
The retroactivity matters more than it first sounds: Google states the dimension "is populated retroactively," so you can analyze historical data with it [1]. You do not need to have configured anything before your AI traffic started arriving; the grouping applies backward to source values you already collected.
The hostname filter is quieter but useful housekeeping: a data filter type that excludes events by hostname [1], which is the clean fix for staging or spam hostnames polluting reports.
Source Group vs the AI Assistant channel: which list covers what?
Here is the two-layer system, because conflating these produces wrong conclusions.
| AI Assistant channel | Source Group dimension | |
|---|---|---|
| Shipped | May 13, 2026 [2] | June 11, 2026 [1] |
| What it is | A default channel group value | A dimension consolidating source values |
| Keyed on | Medium exactly matches ai-assistant [2] |
Source string patterns |
| Named coverage | ChatGPT, Gemini, Deepseek, Copilot, Grok [2] | ChatGPT (OpenAI), Perplexity named in the announcement [1] |
| Perplexity? | No; stays in Referral [2] | Yes [1] |
| Historical data | Forward-facing | Retroactive [1] |
The practical consequence: if you only look at the channel report, Perplexity visits hide inside Referral, mixed with every blog that links you. And Google's channel definition explicitly excludes its own AI surfaces: traffic from AI Overviews and AI Mode does not land in the AI Assistant channel [2]. So neither layer gives you "all AI-driven traffic" in one number. The channel gives you a clean slice of assistant-referred sessions from its five listed sources; Source Group cleans up naming per platform, Perplexity included.
Where do you actually find Source grouping in the UI?
Not where most coverage says. We checked a live GA4 property on July 17, 2026, and the standard Traffic acquisition report's dimension picker returns nothing for "source group." The dimension surfaces in the Advertising workspace: Advertising → Conversions → Conversion performance (a beta report), where the primary-dimension picker lists "Source grouping" under the Cross-channel category. Selecting it re-renders the report as "All conversions by Source grouping."
The walkthrough, on your own property:
- Open GA4 and click the Advertising icon in the left rail.
- Under Conversions, open Conversion performance.
- Click the primary dimension dropdown above the table.
- Search for "source group" and select Source grouping.
- Read the table: each row is one consolidated source with its attributed conversions.
Two expectations to set. First, this is a conversions report, so a source group only appears once it has conversions attributed; on the property we checked, session-level AI traffic existed while the conversion table showed rows like Google Search, Bing, and (direct). Second, the placement may widen. The feature is five weeks old, Google's announcement does not say where the dimension will ultimately surface [1], and everything above is what the UI showed as of July 17, 2026.
Why is part of your AI traffic still invisible?
Because grouping can only consolidate what carried a referrer. A visit from perplexity.ai's website typically arrives as source perplexity.ai, medium referral, and is attributable all day. But traffic from AI-embedded browsers behaves differently: MarTech's testing found that ChatGPT Atlas sessions often appear as Direct, or occasionally as (not set), because in-app and privacy-conscious browsers strip the referrer header [3]. A visit with no referrer and no UTM is Direct, and no dimension released in June changes that.
So read your AI numbers as a floor, not a ceiling. The sessions GA4 labels as AI-assistant traffic are the ones that identified themselves; an unknowable share of the same behavior hides inside Direct. If you want the fuller picture, the complement to your GA4 reports is asking buyers directly, and how Shopify orders end up unattributed in the first place is its own topic, covered in GA4 (not set) and unattributed orders.
Is AI-assistant traffic actually worth a merchant's attention?
Our own data says yes, twice over, with sample-size caveats stated plainly.
First, store traffic. On our own store's GA4 property, the AI Assistant channel is already a standing row in Traffic acquisition: in the 28 days ending July 16, 2026, it recorded 72 sessions with a 56.94 percent engagement rate and $569.63 in attributed revenue. Small next to search, but it is a channel that did not exist as a reporting concept in April, with revenue attached.
Second, commercial discovery. We run an install-attribution survey asking merchants how they found our tracking app. Across the 46 responses collected so far, the top answer is "AI Assistant (ChatGPT, Claude, etc.)" at 18 of 46, or 39.1 percent, ahead of Google at 32.6 percent and Facebook at 19.6 percent. Two disclosures belong in the same breath: it is a multi-select survey, so shares sum past 100 percent, and it measures how merchants discover a Shopify app, not how shoppers reach their stores. But as evidence that AI assistants now route real buying decisions, a plurality of our own responding customers naming an AI assistant is hard to dismiss. If you have wondered whether your customers are asking ChatGPT what to buy: ours told us they are.
The paid side of the same shift is moving too; OpenAI opened self-serve advertising this spring, and we covered tracking OpenAI Ads conversions on Shopify when our integration shipped.
How do you keep an AI-referred purchase from reporting as Direct?
The referral got the visitor to your store; the conversion still has to land in the same session, or attribution breaks at the last step. This failure is structural on Shopify: purchases confirmed by server-side integrations open a fresh GA4 session unless the integration carries the browser session's identity, and a fresh session with no source reports as Direct.
WeltPixel Conversion Tracking handles this by having the server-side purchase reuse the browser session's Client ID and Session ID, so the conversion folds into the session GA4 already attributed to chatgpt.com or perplexity.ai instead of starting a new one. The mechanism and its honest limits (a blocked or never-loaded pixel means there is no browser session to join) are unpacked in why a purchase starts a new GA4 session. Browser events respect Shopify's Customer Privacy API signals throughout.
If AI-referred buyers are showing up in your traffic reports but your revenue still concentrates under Direct, the gap is usually this session join. Install WeltPixel Conversion Tracking and your server-side purchases inherit the session attribution your AI traffic earned, in the same reports where Source grouping now names the assistant that sent them.
FAQ
Does Source Group change my historical reports?
The dimension is populated retroactively, so you can analyze historical data with it [1]. Your raw source and medium values are untouched; the grouping is an additional dimension layered on top, not a rewrite.
Why doesn't Perplexity show up in the AI Assistant channel?
Perplexity is not in the channel's live definition, which lists ChatGPT, Gemini, Deepseek, Copilot, and Grok [2]. Perplexity visits land in Referral at the channel level; the Source Group dimension is what names them.
Will all my ChatGPT traffic now be labeled?
No. Grouping consolidates source values that carried a referrer. Traffic from AI-embedded browsers like ChatGPT Atlas often arrives with the referrer stripped and reports as Direct [3], where no grouping applies.
Do I need to change anything in my tracking setup?
Not for Source Group; it applies automatically and retroactively [1]. The hostname filter from the same release is opt-in in Admin, under data filters, if you want staging or spam hostnames excluded.
Where exactly do I find the Source grouping dimension?
As of mid-July 2026: Advertising → Conversions → Conversion performance, then switch the primary dimension to Source grouping (listed under Cross-channel). It is not offered in the standard Traffic acquisition report's dimension picker today; that may change as the beta matures.
Sources
- Google, "What's New in Google Analytics," Source Group entry, support.google.com/analytics/answer/9164320 (June 11, 2026)
- Google, "Default channel group," AI Assistants definition, support.google.com/analytics/answer/9756891 (accessed July 17, 2026); AI Assistant channel announced in What's New, May 13, 2026
- Dan Taylor, "How GA4 records traffic from Perplexity, Comet and ChatGPT Atlas," MarTech, martech.org/how-ga4-records-traffic-from-perplexity-comet-and-chatgpt-atlas/ (November 4, 2025)