I fetched 3,000 SEO-related queries in the US via SerpAPI to map which domains Google cites in AI Overviews. Only 735 of those queries returned AIO results — this analysis is based on those 735 keywords, with 8,963 total citations, and 2,003 unique domains.
Data source: SerpAPI · Keyword data: Ahrefs Keywords Explorer · Collection date: June 2026
Key Findings
YouTube is the top cited domain in AI Overviews for SEO queries. With 11.4% of all citations, it appears nearly 3× more than the #2 domain (Reddit at 4.5%). Google is actively directing users to its own video platform.
Reddit is the #2 most-cited source at 4.5% of citations. Google continues to reward community-generated content and first-person perspectives in AI answers.
SEO tools and specialist sites account for 15% of cited domains. SEO tools like Semrush (#3), Moz (#5), Yoast (#6), and Ahrefs (#11) appear alongside specialist publications like Search Engine Journal and Search Engine Land — suggesting that dedicated SEO content earns notable AIO visibility.
Google cites its own properties at 2.76% — primarily Google Search Central / Developers docs. When Google cites itself, it's almost always for technical SEO fundamentals.
The top 30 domains — just 1.5% of all cited sources — account for 45% of citations. The remaining 55% is spread across 1,973 domains, with no single content type or site category dominating AIO sourcing.
Video is the #1 cited content format at 11.7% of all citations — virtually all from YouTube. SEO tool blogs follow at 11.1%, and community platforms (Reddit, LinkedIn) at 5.6%. Format matters as much as domain authority.
Citation Frequency
| # | Domain | Citations | % of Total |
|---|---|---|---|
| 1 | youtube.com | 1,025 | 11.4% |
| 2 | reddit.com | 404 | 4.5% |
| 3 | semrush.com | 344 | 3.8% |
| 4 | google.com | 247 | 2.8% |
| 5 | moz.com | 141 | 1.6% |
| 6 | yoast.com | 130 | 1.5% |
| 7 | linkedin.com | 100 | 1.1% |
| 8 | searchengineland.com | 84 | 0.9% |
| 9 | aioseo.com | 68 | 0.8% |
| 10 | searchenginejournal.com | 65 | 0.7% |
| 11 | ahrefs.com | 60 | 0.7% |
| 12 | seoclarity.net | 58 | 0.6% |
| 13 | straightnorth.com | 53 | 0.6% |
| 14 | wikipedia.org | 51 | 0.6% |
| 15 | digitalmarketinginstitute.com | 50 | 0.6% |
| 16 | shopify.com | 49 | 0.5% |
| 17 | seranking.com | 46 | 0.5% |
| 18 | brightedge.com | 46 | 0.5% |
| 19 | americaneagle.com | 45 | 0.5% |
| 20 | mtu.edu | 44 | 0.5% |
| 21 | mailchimp.com | 43 | 0.5% |
| 22 | clickrank.ai | 41 | 0.5% |
| 23 | seo.com | 40 | 0.4% |
| 24 | geeksforgeeks.org | 39 | 0.4% |
| 25 | rankmath.com | 38 | 0.4% |
| 26 | wix.com | 37 | 0.4% |
| 27 | elementor.com | 37 | 0.4% |
| 28 | bruceclay.com | 37 | 0.4% |
| 29 | searchatlas.com | 37 | 0.4% |
| 30 | mangools.com | 33 | 0.4% |
Interpretation and Implication
The 30 most-cited domains account for 45% of all 8,963 citations. This is significant concentration: just 1.5% of cited domains (30 out of 2,003) receive nearly half of all citations.
Google clearly has a preferred set of sources it trusts heavily for SEO topics, yet citation visibility extends across thousands of other domains. The citation ecosystem is concentrated, but not monopolized: Google's trust is focused, but its sourcing is still diverse.
Category Analysis
Keywords were segmented into four topic categories — Technical, Content, Authority, and AI SEO — to compare how citation sources shift by query type.
| Category | Keywords | Citations | Total Vol | Avg Vol | Avg URLs/KW |
|---|---|---|---|---|---|
| Technical SEO | 244 | 3,069 | 150,230 | 616 | 12.6 |
| Content SEO | 244 | 2,950 | 135,010 | 553 | 12.1 |
| General | 139 | 1,683 | 141,890 | 1,021 | 12.1 |
| Authority | 95 | 1,090 | 50,290 | 529 | 11.5 |
| AI SEO | 14 | 171 | 6,480 | 463 | 12.2 |
Interpretation and Implication
YouTube dominates every single category — peaking at 22.8% for AI SEO queries, 13.6% for Content SEO, and never dropping below 9% in any category. No other domain comes close to this consistency.
Google cites its own docs most for Technical SEO — google.com ranks #3 (4.1%) for technical queries, nearly 2× its overall average with Search Central and Developers docs used for technical reference.
Semrush is the #1 non-YouTube source for Content SEO at 5.4% — outranking Reddit, Google, and Yoast. Their blog is Google's most trusted content strategy resource for citation in AI Overviews.
Mailchimp appears in the top 5 for Authority SEO at 2.1% — surprising for a brand known for email. Their SEO and marketing blog earns significant AIO trust for backlink and off-page queries.
Search Engine Land is the #2 source for AI SEO queries at 6.4% — the only category where a news/media publication breaks into the top 3.
Wikipedia makes it to the top 5 most cited domains when the SEO query is broad or very generic. Which is not the case for more specialized SEO queries.
Content Type Analysis
Interpretation and Implication
Video is the #1 content format by share of citations. YouTube alone accounts for 11.7% of all citations — and 99.7% of all video citations. Google is treating video as an important answer format for SEO queries.
SEO tool blogs dominate the "text" category. At 11.1% of all citations, Semrush, Moz, Yoast, AIOSEO, and Ahrefs together outperform every other content category except video. Comprehensive tool-driven content earns outsized trust.
Reddit drives 77% of all community citations. LinkedIn adds 18% — mostly as professional article content. Community-sourced, first-person experience content is a significant and consistent signal Google rewards.
Google's own documentation accounts for 2.5% of citations — almost entirely from developers.google.com. When Google cites itself, it's almost always for technical SEO fundamentals, not general advice.
Industry news sites punch above their weight for AI SEO. Search Engine Land and Search Engine Journal together account for 98% of news citations. Their recency advantage matters most for emerging topics.
62.9% of citations come from thousands of individual blogs, agency sites, and web pages each cited once or twice. This confirms that AIO citations, while partly concentrated, are not monopolized by format or brand size.
Website Specialty Analysis
| Specialty | Citations | % of Total |
|---|---|---|
| Generic & Other Sites | 5,253 | 56.5% |
| General Platforms | 1,929 | 20.8% |
| SEO Specialist Sites | 1,433 | 15.4% |
| Website & Tech Sites | 295 | 3.2% |
| Marketing & Agency Blogs | 260 | 2.8% |
| Academic & Education | 120 | 1.3% |
Interpretation and Implication
Dedicated SEO publishers account for 15.4% of all citations, despite representing only a small slice of the web. Semrush alone contributes nearly a quarter of citations within this group.
A small group of general-purpose platforms — YouTube, Reddit, Google, and LinkedIn — account for 20.8% of citations. Together they outperform the entire SEO-specialist category, suggesting that scale, user engagement, and platform authority can rival subject-matter specialization.
The largest category is neither platforms nor SEO publishers. 56.5% of citations come from more than a thousand smaller domains, including agencies, SaaS companies, ecommerce sites, educational institutions, and niche publishers. No single source dominates this group, but collectively they make up the majority of Google's citation ecosystem.
Google's AI Overviews do not rely on a single type of source for SEO advice. Instead, they draw from a mix of dominant platforms, specialist publishers, community discussions, official documentation, and thousands of smaller websites.
YouTube is the clearest winner. It is the most-cited domain overall, the leading source in every SEO category analyzed, and accounts for nearly all video citations. For SEO topics, Google appears to view video as a first-class answer format rather than a supplementary resource.
Specialized SEO publishers also perform exceptionally well. Semrush, Moz, Yoast, Ahrefs, Search Engine Journal, and Search Engine Land earn a disproportionate share of citations relative to their footprint on the web. Their visibility suggests that deep topical coverage and sustained expertise are strong signals for citation eligibility.
At the same time, AI Overviews are far from closed ecosystems. Reddit ranks as the second most-cited domain overall, while more than half of all citations come from outside the top 30 domains. Across the dataset, Google cited 2,003 unique domains, demonstrating that visibility is not limited to a small group of established brands.
The broader pattern is that Google favors a mix of scalable authority and diverse supporting evidence. AI Overviews frequently combine specialist expertise, community perspectives, official documentation, news coverage, and niche publishers within the same answer. Concentration exists at the top, but diversity remains a defining characteristic of the citation ecosystem.
For SEOs, this creates two viable paths to visibility. One is becoming a recognized authority within a topic through comprehensive coverage and brand strength. The other is publishing highly relevant, deeply useful content that answers specific questions better than competing resources. The data suggests both approaches can earn citations, even though the first scales more predictably.
Methodology