How AI citation actually works.
The quarterly measurement of how AI assistants build their recommendations: which venues each engine cites, by category. Original data, refreshed quarterly. The scorekeeper outlives the players.
Key findings
- ›Reddit is the single most-cited source in buyer AI answers this quarter, at ~31% of cited venues.
- ›Only ~11% of cited domains overlap between ChatGPT and Perplexity. No single content strategy wins the AI surface.
- ›Gemini cites Reddit at ~0.1% while Google AI Mode cites it at ~44%. Citation weight is engine-specific and swings violently.
- ›AI recommendation answers are built from a finite, countable set of community sources, not the open web.
Most-cited venues, Q2 2026
| Category | Presence leader | Share | Biggest open gap | Movement |
|---|---|---|---|---|
| CRM for startups | Pipedrive | 31% | EU data residency | ▼ slipping |
| Email / lifecycle | Customer.io | 24% | Mailchimp migration | ▲ rising |
| AI sales assistants | Clay | 38% | pricing transparency | ▲ rising |
| Community tooling | (open) | 12% | intent vs. keyword | ▬ flat |
| Auth / identity | Clerk | 29% | self-host story | ▲ rising |
Where each engine reads
No single content strategy wins the AI surface. That’s the whole argument.
Wikipedia + Reddit >25%; editorial press heavy; Reddit share volatile
→ Reddit + Q&A + editorial; track continuously
Reddit dominant (~24%); skews LinkedIn, NIH, G2
→ Reddit + G2 / review + LinkedIn for B2B
Reddit ~44% of social cites; classic SEO still converts
→ Reddit + owned-surface evidence + indexed forums
Reddit ~0.1%; rewards traditional SEO + reference authority
→ Owned surfaces, docs, high-authority Q&A
Citation weight moves violently
Retrieval weight per place, last five quarters. A static AI-visibility plan is dead on arrival.
Methodology
We run each category’s buyer query set across ChatGPT, Perplexity, Google AI and Gemini, multiple passes per prompt (answers are probabilistic; one pass is noise), and resolve every cited URL to its canonical venue. Weights are the share of resolved citations per venue, per engine. We publish only what we can measure, refreshed quarterly. Cite this page: grounds · The Grounds Index · Q2 2026.
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