ChatGPT Is Utilizing Google Search – We Examined It

Final month, Abhishek Iyer ran a pointy experiment:

He created a brand-new nonsense time period, acquired it listed solely in Google, after which requested ChatGPT about it.

ChatGPT returned an ideal abstract — even though Bing had by no means seen the web page.

That check acquired our consideration.

So we ran our personal.

We invented a brand new faux search engine optimisation time period, NexorbalOptimization, revealed a devoted web page on Backlinko, and made certain solely Googlebot may crawl it.

Then we waited.

The outcomes confirmed what Abhishek — and a handful of others — have began to suspect:

ChatGPT Plus is utilizing Google Search knowledge. Not simply Bing.

Right here’s how we ran the check, what we discovered, and what this implies for the way forward for AI search visibility.

Step 1: Create a Time period That Doesn’t Exist

We made up a brand new search engine optimisation buzzword: NexorbalOptimization.

It had:

Zero mentions on-line
No search quantity
No overlap with actual phrases, acronyms, or model names

We constructed a brand new web page on Backlinko with fake-but-professional sounding content material explaining what “NexorbalOptimization” supposedly is.

Right here’s the dwell URL: https://backlinko.com/nexorbaloptimization

Step 2: Let Google In (and Block Everybody Else)

Subsequent, we up to date our robots.txt file with the next:

# Permit Googlebot to entry the particular web page
Consumer-agent: Googlebot
Permit: /nexorbaloptimization
# Block all different bots from that web page solely
Consumer-agent: *
Disallow: /nexorbaloptimization

We additionally made certain this URL wasn’t included in our public sitemap.xml file.

That meant:

Googlebot may crawl and index the web page
Bing, Perplexity, DuckDuckGo, Claude, and different bots have been blocked
The web page was invisible to public crawlers and AI instruments, until they have been utilizing Google

We manually submitted the URL to Google Search Console and waited for indexing.

GSC – Inspect – Backlinko – Nexorbaloptimization

Step 3: Await Indexing, Then Ask ChatGPT

As soon as the web page was dwell, it took just a few hours to get listed in Google:

Google SERP – Backlinko – Nexorbaloptimization

We confirmed that it nonetheless wasn’t listed in Bing:

Bing SERP – Backlinko – Nexorbaloptimization

Or DuckDuckGo:

DuckDuckGo SERP – Backlinko – Nexorbaloptimization

Then, we examined a immediate in several LLMs / fashions:

ChatGPT Plus (non permanent chat, with net looking) discovered our web page and quoted it word-for-word:

ChatGPT Free (with net looking, not logged in) couldn’t discover something:

Neither may Claude 4 Sonnet:

Curiously, Perplexity was the one different one which managed to search out it:

Perplexity – What is nexorbaloptimization?

The Outcomes

Solely ChatGPT Plus and Perplexity’s Free plan returned a sound reply based mostly on the Backlinko web page.

All different fashions both:

Returned nothing
Stated the time period didn’t exist
Or made one thing up with out referencing the web page

This confirmed two issues:

Google was the one search engine that knew in regards to the time period
The AI responses mirrored the precise phrasing, construction, and ideas from our made-up web page

Why This Issues

There’s been hypothesis for months that ChatGPT particularly may be counting on extra than simply Bing.

OpenAI has an official partnership with Microsoft.

ChatGPT’s default looking mannequin is usually described as utilizing Bing.

However these experiments inform a special story.

Right here’s what’s changing into more and more clear:

1. ChatGPT Plus is indexing Google Search

Particularly when different engines haven’t seen the web page.

2. search engine optimisation visibility in Google instantly influences AI solutions

In case your web page doesn’t rank in Google, ChatGPT probably gained’t “see” it — no matter whether or not you rank in Bing or not.

3. Google is the trusted supply of fact for LLMs

Not as a result of it’s said — however as a result of it’s listed quicker, deeper, and extra utterly.

What This Means for search engine optimisation within the Age of AI

This check, and others prefer it, reveal one thing important:

AI search visibility is changing into an extension of Google’s dependable index and search visibility.

You’re not simply optimizing to seem in a SERP.

You’re optimizing to be pulled right into a ChatGPT reply field.

Or a Perplexity paragraph.

Or a Gemini-generated comparability.

If Google doesn’t index you — many AI instruments gained’t floor you.

That makes indexation and crawl entry much more strategic than earlier than.

Why LLM Visibility Nonetheless Begins with Google (And Learn how to Observe It)

For those who’re attempting to grasp the place your model exhibits up in AI-generated content material, it is advisable begin with a easy fact:

Google’s index is the inspiration layer for many LLMs.

Whilst instruments like ChatGPT, Claude, and Perplexity generate solutions on the fly, they’re pulling from a mixture of:

Crawled net outcomes (usually from Google-indexed pages)
Structured knowledge
Excessive-authority model mentions

In case your content material isn’t listed — or isn’t rating — it’s invisible to crucial LLMs.

That’s why conventional search engine optimisation fundamentals nonetheless matter:

Crawlability
Quick indexing
Content material structured for semantic readability
Proudly owning your model queries and product phrases

Need to observe your presence in AI instruments?

You’ll want greater than only a rank tracker.

Pondering Forward

As LLMs grow to be extra influential within the discovery course of, you’ll wish to begin monitoring how your model exhibits up throughout instruments — not simply in SERPs.

Which means discovering a device (or set of instruments) that: