What source categories show up most in AI answers? | Trakkr Research
Social is the largest named category at 7.20%, followed by reference at 1.98% and reviews at 1.15%. However, 86.75% remains in “other”, so the source-type taxonomy is incomplete.
Methodology: Built from 48,422,016 citation appearances across 529,165 unique domains in the latest valid snapshot for 1,643 tracked brands, observed from October 3, 2025 to August 18, 2026.
Direct Answer
Social is the largest named category at 7.20%, followed by reference at 1.98% and reviews at 1.15%. However, 86.75% remains in “other”, so the source-type taxonomy is incomplete.
What this means
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.
Evidence table
| Metric | Value | Why it matters |
|---|---|---|
| Reference category share | 1.98% | Partial hand-maintained source classification. |
| Social category share | 7.20% | Social is the largest named category, led by YouTube, Reddit, and LinkedIn. |
| Review category share | 1.15% | Partial hand-maintained source classification. |
| Docs category share | 0.17% | Partial hand-maintained source classification. |
| Unclassified share | 86.75% | Domains outside the current named source map remain in “other”. |
Frequently Asked Questions
What source categories show up most in AI answers?
Social is the largest named category at 7.20%, followed by reference at 1.98% and reviews at 1.15%. However, 86.75% remains in “other”, so the source-type taxonomy is incomplete.
Which numbers from AI Citation Index matter most here?
Reference category share: 1.98%. Partial hand-maintained source classification. Social category share: 7.20%. Social is the largest named category, led by YouTube, Reddit, and LinkedIn.
What should a team do next?
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.
What to do next
Related pages
Continue through the same study cluster.
- do brands need third party sources to win ai citations - Related answer page
- what should a brand prioritize after reading the source data - Related answer page
- wikipedia leads the current citation index - Related fact page
- source category share tracker - Related tracker page
Data & Sources
- AI Citation Index - Flagship study behind this page
- Page JSON - Machine-readable companion file