YouTube Was Cited in Eleven of Our Twelve AI Measurements. Reddit in Six.

We kept noticing the same two domains in results that had nothing else in common. So we counted. Across twelve measurements where we kept the full source list, spanning three markets, three languages and nine categories, YouTube was cited in eleven of them, and in every single run of eight. The only category it never appeared in was fractional CFO services.

Reddit behaves differently and the difference is the useful part.

How this was measured: Google AI Overview, country and language set explicitly on every call, cache bypassed, runs executed serially. Twelve measurements, 36 runs, 5 to 7 August 2026. We count cited domains, not brand mentions. This article uses only the measurements where we retained the complete source list; four earlier ones are in our register with counts but without their domain lists, and they are excluded rather than guessed at.

The count

YouTube: cited in 11 of 12 measurements, stable across every run in 8.

Reddit: cited in 6 of 12, stable across every run in 2.

No other domain in the whole set comes close to that reach. Every other source we saw was specific to its category: Gartner and GitHub for coding tools, four shoe review sites for running shoes, a government guide for French agencies.

Why this is strange

These categories share nothing. Running shoes and fractional CFO services have no vocabulary in common, no audience in common and no publishers in common. Three of the measurements are not even in English.

Yet one video platform appears in almost all of them, usually in every run.

We are not going to claim we know why. What we can say is what it is not: it is not a quirk of one category, one market or one language, because we varied all three and it survived. And it is not a general property of large platforms, because Reddit, which is comparably large and comparably crawled, appears in barely half.

The category that added a second video platform

The twelfth measurement is the newest and it broke a pattern the first eleven had held.

Asked which are the best universities in Paris, in French with France set, Google’s AI Overview cited fifteen domains across four runs. YouTube reached three of the four, which is ordinary. dailymotion.com reached all four, and it is the only time in the whole set that a video platform other than YouTube has been stable in a category.

Set that against what else was stable in the same four runs: a French school for foreigners, a private tutoring firm, a relocation agency, a course directory and Wikipedia. Three university domains appeared, one run each, none of them stable.

So in that answer, two video platforms carried more of the evidence than every university in Paris combined. We wrote that study up separately, because the education finding stands on its own. What it adds here is that the video layer is not one company: in a French-language market, the local video platform did the same job YouTube does elsewhere, and did it better.

What Reddit does instead

Reddit’s absences are more informative than its presences.

It is absent from running shoes, AI coding assistants, Spanish AI visibility tools and French GEO agencies. It is stable in email marketing and CRM, and appears in project management and fractional CFO services.

Look at what the Reddit-free categories have that the others do not:

• Running shoes returned five domains and four of them are independent shoe review sites: runrepeat.com, weartesters.com, solereview.com and womensrunning.co.uk.
• AI coding assistants returned Gartner and GitHub among thirteen.

Both have a settled ecosystem of independent expert publications. The categories where Reddit shows up, CRM and email marketing and project management, are the ones where the alternative is vendor marketing and affiliate listicles.

The working hypothesis, and it is a hypothesis: Reddit surfaces where no trusted independent reviewer exists. When retrieval can reach a specialist publication that is not selling the product, it prefers that. When it cannot, it reaches for people arguing in public.

That is consistent with what we found counting who publishes the “best GEO agency” rankings, where thirteen US agencies each named themselves first and Reddit sat third on the results page. A category whose expert layer is written by contestants sends buyers, and apparently retrieval, to the forum.

The other pattern: software companies as reference works

One more domain appeared in two unrelated categories, in every run of both: zapier.com, stable in project management and in email marketing.

Zapier sells neither. It sells automation, and it publishes comparison content about the tools it integrates with. That content is now doing the job a trade magazine used to do.

The same shape shows up elsewhere in our data. In one of our earliest measurements, thirteen of nineteen domains cited for “how do I track brand mentions in ChatGPT” belonged to companies selling the measurement. We are one of those companies and this article is one of those pages, which is exactly why every number here carries its method.

The practical read: adjacency beats advertising. A company that publishes genuinely useful comparison content about its neighbours gets cited in its neighbours’ categories. That is a content strategy nobody in B2B seems to price correctly.

What we would do with this

Publish video, and not for the video. YouTube reached eleven of twelve measurements here, across nine categories and three languages, usually in every run. Almost no B2B company treats video as a retrieval surface. It is the cheapest thing on this list to start and the only one that appeared nearly everywhere.

Check whether your category has an independent reviewer. If it does, that publication is the citation to win and it is probably reachable through ordinary press relations. If it does not, the forum thread is your category’s reviewer, and pretending otherwise does not help.

Write for the adjacent category, not only your own. Zapier is cited in two categories it does not compete in. That is a much cheaper route to being a cited source than fighting for your own most contested term.

And measure it yourself before believing any of this. Twelve measurements is enough to see a pattern this strong and not enough to give you a rate. The whole method is above: pick your prompt, set country and language explicitly, run it three times, and count what comes back. How many runs you need depends on your category, which we measured separately.

A confirmation we did not plan

The running shoes result is worth its own line, because it lands on a question we asked in a different study.

Five domains cited, all five in every run, four of them independent review sites. It is the most stable category we have measured, more stable than flight booking and more stable than AI coding assistants.

Our stability study proposed that instability tracks the number of roughly interchangeable pages competing to answer, and that categories with a few clearly primary sources return the same ones every time. Running shoes has an unusually strong independent review layer and produced an unusually small, unusually stable citation set. That is consistent with the hypothesis. It is one more observation, not proof, and we are labelling it as such.

What this does not show

• One surface. Google AI Overview only. ChatGPT, Perplexity and Gemini retrieve differently.
• Twelve measurements, 36 runs. Enough to establish that YouTube’s reach across categories is real and large. Not enough for a rate, and not enough to rank categories.
• Presence is not prominence. We counted whether a domain was cited, not how much of the answer it supported or where it sat.
• Which videos, answered since. We have now read the cited URLs: every cited video was a comparison, and the channels we could identify were independent reviewers rather than brand channels.
• Four earlier measurements are excluded because we kept their counts but not their source lists. Including them from memory would have been guessing.
• Nothing causal. We changed nothing. Publishing a video is not demonstrated here to cause a citation.

Common Questions About YouTube and Reddit in AI Answers

Does Google’s AI Overview cite YouTube?

Frequently, and across categories that share nothing else. In our twelve measurements spanning three markets and nine categories, YouTube was cited in eleven and appeared in every single run of eight of them. The only category where it never appeared was fractional CFO services.

Does AI cite Reddit?

Less often and more selectively. Reddit appeared in six of twelve measurements and was stable in two. It was absent from running shoes and AI coding assistants, both of which have established independent review publications, and stable in email marketing and CRM, where the alternative is vendor content.

Should B2B companies publish video for AI visibility?

The data here says video is the single most category-independent surface we have measured, and it is one almost no B2B company treats as a retrieval channel. We would test it. We would not promise a result, because this is an observational count and nothing in it demonstrates that publishing a video causes a citation.

Why would a software company be cited about products it does not sell?

Because it publishes useful comparison content about its neighbours. zapier.com was cited in every run of both our project management and email marketing measurements, and it sells neither. Writing well about an adjacent category appears to be a cheaper route to being a cited source than competing for your own most contested term.

How many runs do I need to check this for my own category?

Three is enough to see whether a domain is stable or occasional, which is what this article counts. It is not enough to publish a rate. The arithmetic, and the finding that the required number varies by category from about three to about thirty, is in our stability study.

Can I reproduce this?

Yes. Every prompt, market, language, date and run count is in our measurement register, and the method is one line: set country and language explicitly, bypass the cache, run each prompt three times, and record which domains the answer cited in each run. If your result differs, the model or the web moved, which is itself worth knowing.