Not sure where to start? Take a guided tour.
AI Site Grader
AI Query Scanner
llms.txt GeneratorWhat source categories show up most in AI answers?
Social is the largest named category at 6.11%, followed by reference at 1.48% and reviews at 1.11%. However, 88.40% remains in “other”, so the source-type taxonomy is incomplete.
The key numbers.
- Reference category share
- Partial hand-maintained source classification.
- 1.48%
- Social category share
- Social is the largest named category, led by YouTube, Reddit, and LinkedIn.
- 6.11%
- Review category share
- Partial hand-maintained source classification.
- 1.11%
- Docs category share
- Partial hand-maintained source classification.
- 0.18%
Named category shares are useful for orientation, but the unclassified majority prevents a full ranking of source types.
The evidence.
Source
AI Citation Index
| Measure | Result |
|---|---|
| Reference category share Partial hand-maintained source classification. | 1.48% |
| Social category share Social is the largest named category, led by YouTube, Reddit, and LinkedIn. | 6.11% |
| Review category share Partial hand-maintained source classification. | 1.11% |
| Docs category share Partial hand-maintained source classification. | 0.18% |
| Unclassified share Domains outside the current named source map remain in “other”. | 88.40% |
Population and method
Built from 80,769,585 citation appearances across 725,777 unique domains in the latest valid snapshot for 1,928 tracked brands, observed from October 3, 2025 to October 14, 2026.
Where the evidence stops
The index is a changing panel of tracked brands and prompts, not a random sample of all AI responses.
Domain share is observational. It does not establish causal influence or reveal the full retrieval set.
The hand-maintained source taxonomy is partial: 88.40% of citation appearances remain in “other”.
Model attribution, response-level citation denominators, geography, raw prompts, and raw responses are not retained in the public aggregate.
What to do with this
- Audit the domains that already dominate your category and decide which ones are realistic citation targets.
- Build source-worthy pages for the query shapes where AI is already citing third parties.
- Treat reference, review, and social sources as part of your AI visibility surface, not as noise.
This answer matters because it turns a study finding into an operating rule teams can use when they decide what to publish, refresh, or measure next.
Questions about this answer.
Cite this answer.
Source study: Citation Sources“Social is the largest named category at 6.11%, followed by reference at 1.48% and reviews at 1.11%. However, 88.40% remains in “other”, so the source-type taxonomy is incomplete.”
Mack Grenfell · What source categories show up most in AI answers?
AI Citation Index · Trakkr Research · Updated 14 October 2026