Google AI features vs ChatGPT search vs Perplexity
Short answer
Google's AI features draw on Google's search index, and sites opt out with a Search Console control. ChatGPT search relies on OAI-SearchBot and Perplexity on PerplexityBot. OpenAI says blocking its bot keeps a site out of search answers; Perplexity only recommends allowing its bot to appear. Of the three, only Google documents a site-owner report, and user-triggered fetchers may ignore robots.txt.
At a glance
Section titled “At a glance”| Google AI Overviews / AI Mode | ChatGPT search | Perplexity | |
|---|---|---|---|
| Crawler that decides inclusion | Googlebot (Google’s search index) | OAI-SearchBot | PerplexityBot |
| Opt out of AI answers only | Search generative AI control in Search Console | Disallow OAI-SearchBot | Disallow PerplexityBot (effect not documented) |
| User-triggered fetcher | — | ChatGPT-User: robots.txt “may not apply” | Perplexity-User: “generally ignores robots.txt” |
| Site-owner report | Generative AI performance report | none documented in these sources | none documented in these sources |
Bing publishes its own citation report for Copilot and Bing AI answers (Bing AI Performance report). It isn’t compared in detail here.
Blocking Googlebot to leave AI features would also remove a site from Search. That is why Google offers the separate control.
ChatGPT search
Section titled “ChatGPT search”Perplexity
Section titled “Perplexity”What this means in practice
Section titled “What this means in practice”- To be eligible everywhere: be indexed by Google, and allow OAI-SearchBot and PerplexityBot in robots.txt and at the firewall (AI search access audit).
- To leave AI answers but stay in Google Search: use Google’s control, and disallow the two search crawlers.
- Training opt-outs (Google-Extended, GPTBot) are separate decisions (Configure robots.txt for AI crawlers).
- robots.txt does not reliably stop user-triggered fetches on ChatGPT or Perplexity. Content that must not be fetched needs access control.