GEO comparison
The LLMs that matter
for SEO and GEO in 2026.
Not all AI assistants weigh the same. Measuring only ChatGPT misses half the map. This is the full comparison of the 8 that matter, with market share, audience, and how to optimize for each.
TL;DR
- ChatGPT dominates with 60-70% of usage. Showing up here is critical, not optional.
- The "second tier" — Claude, Perplexity, AI Overviews — concentrates 25-35% of remaining use with highly qualified audiences (B2B, founders, professionals).
- Each LLM reads different sources: Wikipedia + Reddit + papers for Claude/Perplexity, Bing + LinkedIn for Copilot, Maps + Reviews for Gemini. Your strategy must cover all four categories.
- For local B2C: prioritize ChatGPT + AI Overviews + Gemini. For B2B SaaS: ChatGPT + Claude + Perplexity. For large corporate: add Copilot.
- Mistral and DeepSeek are still niche in 2026 — ignorable except for very specific cases.
Why measuring only ChatGPT leaves you half-blind
Most companies that start taking GEO seriously make the same mistake: measure only ChatGPT. It's understandable — it's the best-known assistant — but it's also an incomplete picture of the market.
ChatGPT leads conversational AI use with around 55% of web visits among assistants (Similarweb, 2026). The rest is split across assistants with different audiences, different information sources, and different citation behaviors — Gemini is already near 27%. Optimizing only for ChatGPT is like doing SEO only for mobile and ignoring desktop.
The four categories you need to cover:
- Generalist conversational: ChatGPT — the big one, mass audience, defines the category.
- AI-powered search: Perplexity + AI Overviews — cite sources with links, highly qualified audience.
- Analytical / technical assistant: Claude — favored by developers, founders, analytical professionals.
- Ecosystem-integrated assistants: Gemini (Google), Copilot (Microsoft) — massive distribution but utilitarian use.
If your brand shows up in ChatGPT but not in Perplexity, you're losing B2B professionals. If it shows up in Claude but not in AI Overviews, you're losing Google traffic. Cross-LLM coverage is the metric that matters — not appearing in only one.
If you're new to GEO, I'd recommend starting with what GEO is and how to measure if you appear.
The 8 AI assistants that matter: full comparison
Estimated market share for 2026, primary audience, strengths and weaknesses, sources each one reads, how to optimize and strategic priority.
ChatGPT
OpenAIMass consumer + generalist professional
Most-used by a wide margin. Its answer defines the category.
Trained model with cutoff — needs active search for recent info.
Wikipedia, Reddit, niche forums, mainstream press, academic publications + real-time Bing web search
Brand mentions on Reddit and Wikipedia + well-attributed answerable content + aggressive schema.org
Critical — not appearing here means invisibility for 65% of GEO traffic
Perplexity
Perplexity AIB2B professionals, founders, journalists, consultants
Cites sources with direct links — the LLM with highest click conversion.
Smaller audience but infinitely more qualified.
Real-time web + Reddit + Twitter/X + academic papers + tier-1 outlets
Authoritative content in outlets Perplexity indexes + X presence + GitHub presence if applicable
High for B2B SaaS, consulting, and professional services. Medium for B2C.
Claude
AnthropicDevelopers, tech founders, analytical professionals
Excellent nuance — captures brand differentiation better than ChatGPT.
No active web search in most usage — depends on its training data.
Training datasets + Common Crawl + books + technical documentation + public GitHub
Open technical documentation + GitHub content + Wikipedia contribution + public papers/whitepapers
High for tech B2B SaaS, developer tools, specialized consulting.
AI Overviews
GoogleAnyone using Google (universal in EN since 2024)
Integrated directly into SERPs — captures users without requiring habit change.
Appears intermittently — Google doesn't show AI Overview for every query.
Classic SEO algorithm + Gemini analyzing top results + schema.org structured data
Well-done classic SEO + aggressive schema.org + answerable content that clearly answers the query
Critical — directly affects Google organic traffic.
Gemini
GoogleGoogle Workspace users, Android, general consumer who prefers the Google ecosystem
Deeply integrated with Google services (Gmail, Docs, Maps, search).
Slower adoption than ChatGPT — Google users tend to search before they converse.
Real-time Google search + Google data (Maps, Reviews, YouTube) + training datasets
Google Business Profile + Google reviews + YouTube presence + classic SEO
High for local B2C (Maps + Reviews weigh a lot) and for businesses with Android audience.
Copilot
MicrosoftMicrosoft corporate professionals (M365), Windows users, Edge browser
Massive distribution via Windows 11 + Edge + Office 365 integration.
Conversational use still limited vs ChatGPT — more utilitarian than exploratory.
Bing search + Microsoft Graph (if authenticated) + LinkedIn (same owner) + training datasets
Bing Webmaster Tools + IndexNow + LinkedIn presence (Person authority) + good schema
Medium. High if your customer is a large enterprise with M365 enterprise.
Mistral / Le Chat
Mistral AIEuropean companies focused on digital sovereignty + European public sector
European model with privacy and data sovereignty emphasis.
Adoption still limited outside France. Grows slowly.
European datasets + Common Crawl + focus on European-language content
Content in European languages + presence in European outlets + documented GDPR compliance
Medium for companies selling to the European public sector. Low for the rest in 2026.
DeepSeek
DeepSeek (China)Specific technical developers + companies with Asian presence
Highly capable open-source models + extremely low cost.
Near-zero adoption by standard consumer or enterprise in Western markets.
Common Crawl + Chinese datasets + GitHub
Only relevant if your business touches the Asian market or technical developers.
Very low for Western markets. Ignore unless specific cases.
How to prioritize by industry
For local B2C (clinic, restaurant, retail)
Priority: ChatGPT (1st) + AI Overviews (2nd) + Gemini (3rd). Your customer searches local on mobile — the Google ecosystem (AI Overviews + Gemini + Maps + Reviews) weighs a lot. ChatGPT rules conversational queries like "best X in my city?".
For B2B SaaS or tech
Priority: ChatGPT (1st) + Claude (2nd) + Perplexity (3rd). Your customer is a founder, CTO or technical decision-maker. They use Claude for deep analysis, Perplexity for pre-purchase research and ChatGPT for everything else. The three together cover almost 100% of the B2B tech decision process.
For professional services (lawyers, tax advisors, consultancies)
Priority: ChatGPT (1st) + Perplexity (2nd) + AI Overviews (3rd). Your customer researches providers before signing. Perplexity with its direct citations is particularly influential because it lets them verify sources — ideal for services where trust decides.
For enterprise B2B with large corporate customers
Priority: ChatGPT (1st) + Copilot (2nd) + Claude (3rd) + Perplexity (4th). In large corporates with M365 enterprise, Copilot already has significant adoption. Cover all four if your sales cycle is long (>3 months) and your customer is a 500+ employee company.
For public sector or European with sovereignty focus
Priority: ChatGPT + Claude + Mistral + AI Overviews. Add Mistral if your customer is a European administration or a company with an explicit focus on digital sovereignty. In 2026 it remains niche, but it's growing.
What to expect in 2026-2027
The AI assistant market is moving fast. Today's shares are not the shares 18 months from now. Trends to watch:
- AI Overviews will gain ground as it expands to every Google query. Gartner estimates traditional search volume will drop 25% by 2026 (Gartner, 2024), with AI answers the main driver.
- Perplexity will grow in B2B as professionals get used to its direct citations. Its native-advertising monetization model will also make it more ubiquitous.
- Claude will gain share among founders and developers thanks to the quality of its analytical responses. Anthropic is investing aggressively in enterprise distribution.
- Copilot will move from 5-8% to 10-15% as Microsoft forces its integration in M365 enterprise.
- ChatGPT will see its share erode from 60-70% to 45-55% — still the big one, but no longer monopolistic.
- New regional players will appear: Mistral will grow in Europe, Chinese models will reach Asia, Indian models will hit the market. Most Western buyers will keep using the big globals.
The practical conclusion: optimizing for multiple LLMs today is building traffic defense for the next 24 months. Anyone who bets only on ChatGPT will be far more vulnerable when the market rebalances.
How to measure your presence in each LLM
The manual method that applies to the big ones (ChatGPT, Claude, Perplexity, AI Overviews, Gemini):
- 20 representative questions for your industry (without mentioning your brand)
- Run each question against every assistant you want to measure
- Three rounds per question (models vary)
- Note in how many responses your brand appears
- Calculate citation rate per LLM and compare
For a full step-by-step methodology: how to know if you appear in ChatGPT (the method works for any assistant).
Manually it's about 4-6 hours per full measurement. To repeat it monthly, tools like our free audit automate the cross-LLM process and keep a history.
Free cross-LLM audit
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