# Google AI features vs ChatGPT search vs Perplexity

> 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.

- URL: https://geo.casa/ai-search/ai-search-platforms/
- Comparison · Officially documented
- Reviewed: 2026-10-26

## 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](https://geo.casa/measurement/bing-ai-performance/)). It isn't compared in detail here.

## Google

> **Officially documented:**
> To be eligible as a supporting link in AI Overviews or AI Mode, a page must be indexed and eligible to be shown in Google Search with a snippet. There are no additional requirements, and no special schema.org structured data is needed.
>
> Sources: [Google Search Central: AI features and your website](https://developers.google.com/search/docs/appearance/ai-features)

> **Officially documented:**
> The Search generative AI control in Search Console excludes a site from AI Overviews, AI Mode and generative AI features in Discover. It "isn't used as a ranking or inclusion signal affecting other parts of Search".
>
> Sources: [Google Search Console Help: Search generative AI control - Search Console Help](https://support.google.com/webmasters/answer/16908024)

> **Officially documented:**
> The Generative AI performance report "shows data about how your site performs in generative AI features on Google Search".
>
> Sources: [Google Search Console Help: Generative AI performance report (Search) - Search Console Help](https://support.google.com/webmasters/answer/16984139)

Blocking Googlebot to leave AI features would also remove a site from Search. That is why Google offers the separate control.

## ChatGPT search

> **Officially documented:**
> OAI-SearchBot surfaces websites in ChatGPT's search features. "Sites that are opted out of OAI-SearchBot will not be shown in ChatGPT search answers, though can still appear as navigational links." OpenAI notes that systems take about 24 hours to adjust after a robots.txt update.
>
> Sources: [OpenAI: Overview of OpenAI crawlers](https://developers.openai.com/api/docs/bots)

> **Officially documented:**
> GPTBot is a separate setting for training. Disallowing it signals that a site's content should not be used to train generative AI foundation models, and it does not affect search. ChatGPT-User visits pages for user actions; "Because these actions are initiated by a user, robots.txt rules may not apply."
>
> Sources: [OpenAI: Overview of OpenAI crawlers](https://developers.openai.com/api/docs/bots)

## Perplexity

> **Officially documented:**
> PerplexityBot surfaces and links websites in Perplexity's search results, and is not used to crawl content for AI foundation models. Perplexity-User fetches pages when users ask questions. "Since a user requested the fetch, this fetcher generally ignores robots.txt rules."
>
> Sources: [Perplexity: Perplexity crawlers](https://docs.perplexity.ai/docs/resources/perplexity-crawlers)

## 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](https://geo.casa/playbooks/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](https://geo.casa/crawling-indexing/robots-txt-ai-crawlers/)).
- robots.txt does not reliably stop user-triggered fetches on ChatGPT or Perplexity. Content that must not be fetched needs access control.

## Sources

- [Google Search Central: AI features and your website](https://developers.google.com/search/docs/appearance/ai-features)
- [Google Search Console Help: Search generative AI control - Search Console Help](https://support.google.com/webmasters/answer/16908024)
- [Google Search Console Help: Generative AI performance report (Search) - Search Console Help](https://support.google.com/webmasters/answer/16984139)
- [OpenAI: Overview of OpenAI crawlers](https://developers.openai.com/api/docs/bots)
- [Perplexity: Perplexity crawlers](https://docs.perplexity.ai/docs/resources/perplexity-crawlers)