US AI Overviews, in the Ahrefs snapshot updated 2 September 2026, cite platforms. YouTube is first at 22.9% of the top-source pool, then Reddit at 18.5%, Facebook at 10.1%, and google.com at 8.8%. Wikipedia is seventh at 4.0%. News brands in that head are under 1%. The Gemini app's list is a different page.
- YouTube leads the US all-topics list at 22.9% of top-source citations and 1.7 million pages. The top 10 were unchanged versus the prior month.
- Those ten are about 82% of the top-50 citation mass. That is concentration inside the head Ahrefs publishes. It is not 82% of every AI Overview link.
- google.com is a top-five source at 8.8%. The table does not say which Google URLs those are.
- Publishers are real and small once YouTube and Reddit are in the denominator. Forbes and Healthline are at 0.8%. The New York Times is at 0.5%.
- A July 2026 Ahrefs cut carried in the French edition had the same order and a slightly lower YouTube share, 21.1%. The page says Wikipedia leads in Belgium and Switzerland for French, Dutch, and German. The US order is not the world's.
The US list
Ahrefs Brand Radar, United States, all topics, page updated 2 September 2026. The sample is described as every domain cited across over 3 million US queries. Mention share divides by the top sources. Partial The query list is Ahrefs', and the denominator inflates every percentage relative to a share of all links.
| Rank | Domain | Mention share | Pages cited |
|---|---|---|---|
| 1 | youtube.com | 22.9% | 1,737,252 |
| 2 | reddit.com | 18.5% | 830,641 |
| 3 | facebook.com | 10.1% | 514,175 |
| 4 | google.com | 8.8% | 1,220,228 |
| 5 | instagram.com | 5.6% | 277,245 |
| 6 | quora.com | 4.7% | 171,198 |
| 7 | en.wikipedia.org | 4.0% | 88,400 |
| 8 | tiktok.com | 3.3% | 140,750 |
| 9 | amazon.com | 3.3% | 148,116 |
| 10 | walmart.com | 1.0% | 47,425 |
Ranks 11 to 20 are mostly US retailers, auto, and health. Home Depot, Forbes, and Healthline at 0.8%. eBay, Edmunds, NerdWallet, Kelley Blue Book, TripAdvisor, LinkedIn, and JustAnswer between 0.7% and 0.6%. News is thin: Business Insider 0.5% at rank 24, the New York Times 0.5% at 26, CNET 0.4% at 29, CNBC 0.3% and new to the top 50 at 44. WebMD is 0.5%. PubMed Central is 0.4%.
An older Profound window, August 2024 to June 2025, counted share of all citations and found a much flatter head: Reddit 2.2% of all AI Overview citations, YouTube 1.9%, Quora 1.5%. Quora was 14.3% of that engine's top 10. The class-level "YouTube and multimodal" figure carried on the AI Overview statistics page is not YouTube's domain share. Do not swap them.
Mention share is not a share of every link
LLM Pulse, the week ending 1 October 2026, counts answers that cite a domain at least once. YouTube is still first, at 33.75% of AI Overview answers, then Facebook 19.34%, Instagram 14.35%, Reddit 14.08%. Country is not stated. The two trackers agree that YouTube leads and that Wikipedia is far behind the platforms. They disagree on Reddit versus Meta. That is what two denominators and an unstated country mix should do.
Promptwatch's June 2026 share of all citations is the small-number version of the same cast: YouTube 4.16%, Reddit 2.72%, google.com 2.30%, Quora 0.24%, Wikipedia 0.15%. A share of every link will always look modest next to a share of the top 50. Both can be honest. Only one of them is "YouTube is a fifth of AI Overviews."
Ahrefs' 2 March 2026 overlap study is a third cut. Of 4 million AI Overview URLs, 37.10% ranked in Google's organic top 10, 26.20% ranked 11 to 100, and 36.70% did not rank in the top 100. YouTube was 5.6% of all cited URLs and 18.2% of the URLs that sat outside the top 100. Classic rank and citation are related. They are not the same list.
Branded queries are a fourth cut. Of 232.8 million US desktop SERPs from July to September 2026, AI Overviews were on 82.91% of branded-keyword results by 29 September. In a panel of 100 brands, the most common external citations were Wikipedia in 41 overviews (71.9% of that panel), YouTube in 22 (38.6%), LinkedIn in 13. A brand query is a different population from the 3 million general queries. Wikipedia leads there because the question is often "who is this company."
The US order is not global
Ahrefs Japan, September 2026, says YouTube stayed first in AI Overviews from the June edition to the September edition. The combined five-engine ranking on that page, ChatGPT plus AI Mode plus Overviews plus Perplexity plus Copilot, is a merge. Wikipedia first, google.com second, YouTube down to fifth. Do not paste the merge into a Google column.
The French edition of the July US-style cut says Wikipedia leads in Belgium and Switzerland for French, Dutch, and German. France was not in that table. A platform list is what a large English-language consumer sample looks like. It is a bad template for a market whose encyclopedia outranks the video site.
What this does not prove
It does not prove that most how-to overviews cite YouTube. A figure of about 1,777 how-to overviews was not found in any public page opened for this series. The closest small check is Windsor.ai's own list: YouTube in 48 of 57 how-to overviews. That is 57 queries, and they are the site's queries.
It does not prove a timestamp rate. A secondary summary of Otterly says that when a YouTube citation carries a timestamp, 73% of those timestamped citations are on AI Overviews and 27% are on AI Mode. That is how timestamped citations split between two Google surfaces. It is not "73% of Overview citations point at a time." The video cut is on most-cited video domains.
And it does not say the overview was supported by the page it cited. A Washington University audit of 55,393 searches in March and April 2026 found about 11% of verifiable claims unsupported or contradicted, and told readers to treat 11% as an upper bound, partly because YouTube and Reddit were hard to capture. Those two domains are the head of this list. The error rate on the sources that dominate the table is the hole in the audit, not a small footnote.
How to use the list
If the query is general and American, the citation is likely to be a video, a thread, a Meta post, or a Google URL. A text page can still be cited. It will not be the plurality. The practical version is a page that can stand next to a video, not a page that pretends to be one.
If the query is a branded navigational search, start from the 100-brand panel instead. Wikipedia and YouTube lead that set, and the percentages are shares of brands, not of the open web. AI Mode's list, where Reddit and YouTube are tied and google.com is heavier, is the next page: most-cited domains in Google AI Mode.
YouTube is 22.9% of the US AI Overview top-source pool. That is not 22.9% of every citation, and it is not the Gemini app.
Share on XVerification status
The ranked ten is Ahrefs' US September page. LLM Pulse and Promptwatch are labelled with their own metrics. A BrightEdge "29.5%" YouTube figure was not opened from a BrightEdge page and is not used. The 1,777 how-to check was not found. This site has not collected its own Overview panel.
Namdev, R. (2026). Most-cited domains in Google AI Overviews (v1). Retrieved from https://ritiknamdev.com/blog/most-cited-domains-ai-overviews Published under CC BY 4.0 — reuse freely with attribution.
AI Mode is a different list. The older class-level figures stay on Google AI Overview statistics.