AI Referrers
Which AI platforms send real human traffic to your site, and how Visibility Kit identifies them.
When a human clicks a link from an AI chat interface, their browser sends a referrer header. Visibility Kit's tracking script reads that header and classifies the visit into an AI source.
Platforms we identify
Each platform has one or more known referrer domains. A visit from any of them is logged as an AI-sourced session.
| Platform | Referrer domain(s) | Source key |
|---|---|---|
| ChatGPT | chatgpt.com, chat.openai.com, openai.com | chatgpt_ai |
| Claude | claude.ai | claude_ai |
| Gemini | gemini.google.com, bard.google.com | gemini_ai |
| Perplexity | perplexity.ai | perplexity_ai |
| Copilot | copilot.microsoft.com | copilot_ai |
| Meta AI | meta.ai | meta_ai |
| DeepSeek | deepseek.com | deepseek_ai |
| Grok | grok.x.ai, x.com/i/grok | grok_ai |
| You.com | you.com | you_ai |
| Phind | phind.com | phind_ai |
| Brave Search | search.brave.com | brave_ai |
| Kagi | kagi.com | kagi_ai |
What gets logged
Each referral session records:
- The AI source (which platform sent the visit).
- The landing page URL.
- Browser and device context (user-agent, viewport).
- Timestamp.
- An anonymized visitor ID for session continuity.
What does not get logged
- The user's prompt to the AI. AI platforms don't pass the prompt in the referrer. It stays on the AI side.
- Which specific AI answer cited your site. Same reason.
- Personally identifiable information about the visitor.
Session continuity
When an AI-referred visitor navigates to other pages on your site, subsequent pageviews are attributed to the same AI-sourced session, the same way Google Analytics maintains organic search sessions. The referrer chain is preserved for as long as the session stays active.