13.7% of AI referral page views come from Claude.

Use the same source domains, but measure the entrance page and the conversion event in one funnel. This keeps referral volume separate from what visitors did after the click.

Referral and landing-page report

1. Open Web analytics, set the last 30 days, and review Acquisition or Referrers for the AI source domains in the table below.
2. Compare visitors, sessions, views, and conversion goals by referring domain. Keep broad aliases separate until you have checked the raw values.
3. Open Product analytics and create a funnel. Make the first step $pageview, filtered where $referring_domain matches the AI source regex.
4. Use your real signup, lead, checkout, or purchase event as step two. Break down the entrance $pageview by $pathname to compare landing pages.

PostHog fields to use

Referrer

$referring_domain on the entrance $pageview

Source filter

Matches the same anchored AI domain regex used for GA4

Landing page

$pathname on the filtered entrance $pageview

Conversion

Your real lead, signup, checkout, or purchase event

First touch

$initial_referring_domain only when the question is first acquisition, not the current visit

Filter the entrance event, not every funnel step. A conversion event may not carry the original referrer property.

Values recognized by the current panel

claude.ai, www.claude.ai, claude, anthropic

Operational rule

Keep the raw source dimension in exports so a broad alias can be removed later without rebuilding the report.

• Treat claude.ai as the high-confidence source. The bare anthropic alias can include manually tagged campaigns that did not come from Claude.
• A click opened through an app, redirect, or privacy-preserving browser can lose its referrer and appear as Direct.
• GA4 does not expose the Claude prompt or answer behind the click. Use landing-page changes and your own conversion events as separate evidence.

Keep blind spots and bots in separate reports

• In-app browsers, app-to-browser handoffs, redirects, privacy settings, and referrer policies can strip the source. Those visits can appear as Direct or have an empty referrer.
• Gemini referrals can show as gemini.google.com, but Google AI Overviews and some AI Mode clicks can remain google / organic. Standard web analytics cannot reliably isolate them from conventional Search clicks.
• Treat dark AI traffic as an unmeasured remainder, not a number to relabel. Report identifiable AI referrals as the observed minimum and keep Direct and unassigned movement as a separate watchlist.
• A source domain identifies the sender when the referrer survives. It does not reveal the prompt, answer, citation, or citation position that caused the click.
• AI crawlers are bots, not human referrals. Keep crawler activity in server or CDN logs, and exclude known bots and internal traffic from visit and conversion reporting.