Do AI engines cite their own websites?

A page citation is one cited page in one AI answer. The matched prompt set is the same organic prompts run on both engines. Ownership is assigned by registered domain, never by brand name, because brand names collide: Gemini is also the name of a crypto exchange.

Google AI Mode cited at least one Google-owned page on 15,100 of 18,350 matched prompts, or 82.3%. ChatGPT Search did so on 2,032 of the same 18,350 prompts, or 11.1%. That is 7.4 times as many prompts. Two separate ways of counting returned identical numbers.

Google-owned pages account for 194,560 of Google AI Mode's 3,075,112 citations in the matched prompt set, or 6.3%. They account for 5,660 of ChatGPT Search's 1,024,634, or 0.55%.

The ratio is 11.5 to 1. Put another way, about one Google AI Mode citation in 16 points to a page Google owns, against about one in 181 for ChatGPT Search.

Of Google AI Mode's citations in the matched prompt set, YouTube accounts for 6.1%, Google product and documentation sites for 0.19%, and google.com itself for 0.006%.

The equivalent ChatGPT Search shares are 0.079% for YouTube, 0.45% for product and documentation sites, and 0.020% for google.com. Set video aside and ChatGPT Search cites Google-owned pages slightly more often than Google AI Mode does, 0.47% against 0.19%.

A search engine sometimes returns a link on its own host in place of the page it is citing. Two shapes appear in Google AI Mode answers: a link back into a Google results page, and a wrapper that redirects to the real page without naming it. Neither is a source, so neither is counted here.

Together they were 5.0% of everything Google AI Mode returned in this window, 4.1% result-page links and 0.8% redirect wrappers. On ChatGPT Search they were 0.001%. An earlier version of this study counted them, which put Google-owned pages at 11.0% of Google AI Mode citations instead of 6.3%, and google.com second on the source leaderboard instead of outside its top 100.

If one engine simply cited large sites more often, every large domain would move the same way. Domain groups owned by neither engine do the opposite: apple.com runs 0.75, reddit.com 0.65, microsoft.com 0.28, and wikipedia.org 0.19, meaning ChatGPT Search cites all four more often than Google AI Mode does.

Google-owned pages run 11.5 times more common on Google AI Mode. OpenAI-owned pages run 0.10, meaning ChatGPT Search cites them 10.0 times more often. Amazon is the one other elevated group at 9.59.

Google product and documentation sites account for 0.45% of ChatGPT Search citations and 0.19% of Google AI Mode citations, or 2.4 times more. On cloud.google.com, ChatGPT Search recorded 1,268 citations against Google AI Mode's 924. On workspace.google.com it recorded 355 against 167, and on developers.google.com 218 against 170.

Google's engine sends readers to Google's video platform. The competing engine sends them to Google's documentation.

Google AI Mode cited youtube.com 188,613 times across 14,891 of the 18,350 matched prompts, or 81.2% of prompts. ChatGPT Search cited youtube.com 809 times, on 500 prompts. The next Google-owned domain, play.google.com, is 68 times smaller on Google AI Mode.

google.com itself is almost absent once its own result pages are excluded: 186 citations on 49 prompts, against ChatGPT Search's 207 on 89. One property, the video platform, accounts for nearly all of the difference between the engines.

On a matched set of 17,723 prompts, Google AI Mode recommended an Alphabet-owned brand on 2,687 prompts, or 15.2%, and ChatGPT Search on 2,591, or 14.6%. The ratio is 1.04.

At the product level the two engines are close on almost every brand. Google AI Mode named Google on 589 prompts and ChatGPT Search on 597. Google AI Mode named Google Cloud on 254 against 259, and Google Workspace on 207 against 233. ChatGPT Search named Looker on 130 against 52 and Google Cloud BigQuery on 113 against 49.

ChatGPT Search cited an OpenAI-owned page on 436 of 18,350 prompts, or 2.4%, against Google AI Mode's 145, or 0.79%. The ratio is 3.01. At the citation level the shares are 0.11% and 0.011%.

Both engines lean toward their owner's properties, but the magnitudes are not comparable. Alphabet operates YouTube; OpenAI operates few content properties.

The matched set keeps 18,350 of the 18,537 prompts that drew a citation in the window, dropping 187 seen on only one engine. Removing the restriction moves Google AI Mode's Google-owned citation share from 6.33% to 6.32% and leaves ChatGPT Search's at 0.55%, so the matched set is not producing the result.

Ownership is assigned by registered domain, so an owned property on an unrelated domain is not counted. Google AI Mode records roughly three times as many citations in the matched prompt set as ChatGPT Search, which is why every comparison uses each engine's own share rather than raw counts.

Google AI Mode cited a Google-owned page on 82.3% of prompts against ChatGPT Search's 11.1%, almost all of it YouTube, while brand recommendations sat at 15.2% against 14.6%.

Track citation share and recommendation share as separate measures, per engine. Treat video as something that matters on Google AI Mode specifically, because YouTube reached 81.2% of prompts there and 2.7% on ChatGPT Search. Keep product documentation current, because documentation is what earned citations on the engine the parent company does not operate. Do not read a rival's citation count on one engine as evidence that the engine recommends them.