01Platforms
Four platforms, four different source landscapes
ChatGPT, Google AI Overviews, Gemini and Perplexity each decide which sources to use in their own way. Being cited well on one says very little about the others, which is why Searlixa measures and reports each platform separately.
The number that drives our whole reporting approach: in a 2026 study of 1,645 AI citations, the two most similar platforms shared only 24.1% of the pages they cited. Every other pair overlapped less. ChatGPT's exclusive citation rate was 73.5% — most of what it cited was cited by nothing else in the sample.
A blended "AI visibility score" averages that away. It is the one thing you can act on.
What varies between them
Five things, and each one changes where a budget should go.
| Platform | How it retrieves | Attribution | What matters most | Speed of feedback |
|---|---|---|---|---|
| AI Overviews | Grounded in Google’s index and ranking | Consistent | Core SEO strength; answer-first structure | Weeks |
| ChatGPT | Own retrieval, highly exclusive selection | Inconsistent | Third-party sources, reviews, comparison pages | Weeks to months |
| Perplexity | Retrieval-led, citation-forward | Heavy, by design | Extractable claims, specificity, recency | Fastest |
| Gemini | Mixed grounding plus model knowledge | Partial | Entity consistency across your whole footprint | Slowest |
Five differences worth budgeting around
- Where the sources come from. Some ground in a search index; others run their own retrieval over a different corpus entirely.
- Whether they attribute at all. A large share of assistant answers name no source. Perplexity attributes heavily; Gemini often does not.
- Which crawler needs access. Each platform has its own agents, and some run separate agents for search discovery and model training. Getting this wrong is the cheapest and most common self-inflicted problem we find.
- How stable the answer is. All are non-deterministic, and one 2026 analysis found only about 30% of brands appearing in one answer stayed visible in the next.
- Where your buyers actually are. This differs by market and industry, and it should decide where the budget goes rather than which platform is in the news.
How we use these pages
Each platform page describes observable behaviour and what it changes about measurement. The optimisation work itself lives in AI Search, GEO and AEO, because most of it is shared across platforms. We keep them separate so that neither page pretends there is a distinct playbook for each assistant.
Terms used across these pages are defined in the glossary, including which describe genuinely different things and which are synonyms.
Observed Behavioural descriptions come from our own sampling plus published 2026 research. Platform behaviour changes without notice and is re-verified each cycle.
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