Unlike top search engines, ChatGPT does not maintain an index of global websites. It has relied instead on Bing’s index and search for training and sources. However, recent third-party tests suggest ChatGPT has switched to Google for that purpose.
An ex-Googler and web developer in India, Abhishek Iyer, summarized his test on X. He invented a meaningless word with a definition, placed them on a page that was neither linked internally nor externally, and submitted the page to Google through Search Console.
He then prompted ChatGPT to define the term. The response was “verbatim” from his web page. He searched for the same word on Bing, DuckDuckGo, and Yandex. None returned results.
Another test, by Aleyda Solís, a search engine consultant, produced similar results. But it also revealed that ChatGPT utilized Google’s search snippet to fetch information.
In a response to a Solís prompt, ChatGPT stated it used “a cached snippet via web search” to fetch the information, indicating that ChatGPT may have direct access to Google’s cache.
In short, ChatGPT appears to utilize Google’s index to find information and sources.
What does it mean for visibility in ChatGPT?
ChatGPT has apparently switched from using Bing’s search index to Google’s.
Google’s Index
Both tests reveal ChatGPT’s reliance on Google’s index, like Google’s own Gemini and AI Mode. Hence being indexed by Google is a key step for visibility in generative AI platforms.
Yet Google is now aggressively removing pages from its index. It’s essential to monitor the indexation status of your important pages. “Crawled but not indexed” statuses in Search Console are more frequent. There’s little chance unindexed pages will surface in genAI responses.
If you are experiencing indexing glitches:
- Know when to ignore them. All sites have unindexed pages. There’s often no problem to solve. It could be near-duplicate pages, old or outdated pages, or pages generated by internal search or filtering. Unless it’s an important product or landing page, “crawled but not indexed” is likely temporary.
- Improve internal linking. A site’s navigation structure is the first step to better indexation. AI-powered tools can help, but overall, tactics such as “Related products,” “Related categories or subcategories,” and product-bundling pages elevate deeper pages.
- Produce unique content. Repeated content can prevent a page from being indexed. It often occurs on sites with extensive products and manufacturer-provided descriptions. Third-party tools can create unique descriptions. Merchants can also follow Amazon’s example and include unique summaries and takeaways on product pages for additional informative content.
Beyond Indexing
Indexation by Google is fundamental, but a strategy for visibility in AI answers is much more. I’ve seen no evidence that organic rankings impact answers in ChatGPT or Gemini. Higher organic rankings do not improve visibility.
GenAI algorithms rely on different signals than search engines, preferring pages that answer questions clearly and succinctly.
Thus ensure your pages:
- Provide straightforward answers to frequent questions,
- Have content easily crawled and accessed with JavaScript disabled — AI crawlers cannot render JavaScript.