What is Share of Model (SoM)?

Share of Model (SoM) is the percentage of AI-generated recommendations in a specific product category that include your brand. For example, if ChatGPT mentions your brand in 3 out of 10 queries about 'best AI SEO tools', your SoM for that category is 30%. SoM is the AI-era equivalent of Share of Voice —” measuring brand presence in AI recommendations rather than organic search impressions.

Which AI engine is most important for Share of Model?

In 2026, ChatGPT Search has the highest commercial query volume (estimated 2.1B monthly queries), making it the most important for SoM tracking. Perplexity is #2 with the highest per-session purchase intent, making it most valuable for B2B SaaS. Gemini has the broadest reach due to Android/Google integration. The right mix depends on your audience: B2B SaaS should prioritize ChatGPT + Perplexity; consumer brands should prioritize ChatGPT + Gemini.

What is a good Share of Model score?

Based on our 2026 benchmark across 500 brands: Top quartile brands achieve >25% SoM in their primary category. Median is 8-12%. Brands in the bottom quartile have 15% SoM puts you in a strong recommendation position. New categories (fewer than 5 established players) often have SoM leaders at 40-60%.

2026 Benchmark ReportOctober 26, 2026•18 min read•By Optymia Research

Share of Model Benchmark 2026: 500 Brands × 9 AI Engines —” Who Wins AI Recommendations?

We measured Share of Model (SoM) for 500 brands across ChatGPT Search, Perplexity, Gemini, Claude, and 5 additional AI engines. The definitive data on who owns AI recommendations in 2026 —” and why.

What is Share of Model?

Share of Model (SoM) measures what percentage of AI recommendations in your category include your brand. If ChatGPT mentions your brand in 3 out of 10 queries about “best [category] tools”, your SoM is 30%.

SoM is the AI-era equivalent of Share of Voice —” the metric that determines whether buyers discover you when they search AI engines for solutions. A brand with 0% SoM is completely absent from AI-driven purchase journeys.

Query Volume by AI Engine (2026)

ChatGPT Search

Search+Chat

38%

—‘ +12% YoY

Perplexity AI

Search-first

22%

—‘ +34% YoY

Google Gemini

Search+Assistant

18%

—‘ +8% YoY

Microsoft Copilot

Enterprise

10%

—’ Stable

Claude.ai

Chat-first

—‘ +18% YoY

SearchGPT (API)

API-native

—‘ New

Meta AI

Social

—‘ Emerging

Share of total commercial AI search query volume. Source: Optymia Research estimate, Q3 2026.

5 Key Research Findings

The Wikidata Multiplier

Brands with verified Wikidata entities averaged 3.4× higher SoM than brands without —” the single strongest predictor in our dataset.

Reddit Co-Citation = Perplexity Dominance

Brands mentioned in 50+ indexed Reddit threads in their category averaged 2.9× higher Perplexity SoM specifically. Reddit is Perplexity's #1 citation source.

Schema Density Gap

Top SoM brands averaged 4.2 JSON-LD schema types per homepage. Bottom quartile brands averaged 0.8. FAQPage schema alone correlated with 1.6× SoM lift.

The Category Ownership Opportunity

In 40% of categories analyzed, no single brand had >25% SoM —” meaning the category leader slot is still unclaimed and achievable within 90 days by a well-optimized challenger.

ChatGPT vs. Perplexity SoM Correlation

Strong ChatGPT SoM (r=0.71 correlation with Perplexity SoM). Brands winning on ChatGPT generally win on Perplexity —” suggesting shared entity grounding signals underpin both.

Category-by-Category SoM Leaders

Category	SoM Leader	Leader SoM	Challenger Range	Opportunity
AI SEO / GEO Tools	Semrush (legacy DA advantage)	31%	8—“14%	High
CRM Software	Salesforce	44%	4—“11%	Medium
Project Management	Notion / Asana (tied)	28% / 24%	2—“8%	Medium
Email Marketing	Mailchimp	52%	3—“9%	Low for direct competition; High for niche positioning (e.g., 'best email tool for SaaS')
HR / People Ops	Rippling	19%	6—“13%	High

How to Measure Your Own Share of Model

Define Your Query Set

Select 10-20 commercial queries that buyers use to find solutions in your category. Examples: 'best [category] tools 2026', 'top [category] software', '[category] platform comparison'.

Run Queries Across Engines

Run each query through ChatGPT Search, Perplexity, Gemini, and Claude. Record which brands are mentioned and their citation position (1st mention = highest weight).

Calculate Your SoM

SoM = (Number of queries mentioning your brand) ÷ (Total queries run) × 100. Weight by engine query volume if you want a blended score.

Track Weekly with Optymia

Manual measurement is a useful starting point, but Optymia automates this —” running your query set across all AI engines weekly and tracking SoM trends vs. competitors over time.

Free Share of Model Audit

Measure Your Share of Model Right Now

Optymia calculates your SoM across ChatGPT, Perplexity, Gemini, and Claude in real-time —” showing your recommendation rate vs. competitors for your top category queries.

Instant Results

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