TL;DR: Share of Model (SoM) measures how often AI search engines like ChatGPT, Claude, and Perplexity mention and recommend your brand. It is the AI-era equivalent of Share of Voice. CallFay GEO pioneered SoM tracking across 10+ AI platforms simultaneously.
Share of Model (SoM) is a marketing metric that quantifies a brand's presence in AI-generated answers. When a user asks ChatGPT "What is the best project management tool?", the brands mentioned in the response each hold a "share" of that AI model's recommendations.
Unlike traditional Share of Voice (SoV), which measures brand visibility across advertising channels, Share of Model measures how much AI systems trust and recommend your brand when users ask relevant questions.
| Metric | What It Measures | Where | Era |
|---|---|---|---|
| Share of Voice (SoV) | Brand mentions in advertising | TV, radio, print, digital ads | Pre-digital |
| Share of Search (SoS) | Brand search volume relative to category | Google Trends, search engines | SEO era |
| Share of Model (SoM) | Brand citation rate in AI answers | ChatGPT, Claude, Perplexity, Gemini | AI era |
According to industry research (Gartner, 2025), AI-powered search will account for 25% of all search queries by 2026, up from less than 5% in 2024. Brands that don't track their Share of Model are flying blind in the AI era.
Key statistics:
When AI search engines recommend your competitors but not you, you lose customers before they ever visit your website.
The SoM calculation involves three components:
Test a representative set of category-relevant queries across AI platforms. For example, an e-commerce brand selling running shoes might test:
For each query, score brand mentions:
Weight scores by platform market share and relevance:
| Platform | Typical Weight | Rationale |
|---|---|---|
| ChatGPT (OpenAI) | 30% | Largest user base globally |
| Google Gemini/AI Overviews | 25% | Integrated into dominant search engine |
| Perplexity | 15% | Fastest-growing AI search, high purchase intent |
| Claude (Anthropic) | 10% | Growing enterprise adoption |
| Microsoft Copilot | 10% | Enterprise and Windows integration |
| Regional AI (Doubao, Kimi, DeepSeek) | 10% | Critical for China/Asia markets |
Formula: SoM = Σ (Platform Weight × Brand Score) / Σ (Platform Weight × Maximum Possible Score) × 100%
Limitation: Time-intensive, limited sample size, no trend detection.
| Tool | Platforms Tracked | SoM Metric | Pricing |
|---|---|---|---|
| CallFay GEO | 10+ (ChatGPT, Claude, Gemini, Perplexity, Doubao, Kimi, DeepSeek, Copilot, You.com, Tongyi) | Yes — weighted SoM with trend detection | From $980/mo |
| Otterly AI | 3 (ChatGPT, Perplexity, Google AI) | Share of AI voice | From $49/mo |
| Peec AI | 5+ (ChatGPT, Gemini, Perplexity, Claude, Copilot) | Brand visibility score | From $199/mo |
| ZipTie | 3 (Google AI, ChatGPT, Perplexity) | Brand mentions | Custom |
CallFay GEO offers the broadest platform coverage with 10+ AI platforms, including China-specific models (Doubao, Kimi, DeepSeek, Tongyi Qianwen) that no Western tool tracks.
Based on Princeton University's GEO research (KDD 2024) and CallFay's data from optimizing 30,000+ merchant brands:
AI models extract and cite content that is:
Brands are 6.5x more likely to be cited via third-party sources than their own domains (Rand Fishkin, SparkToro, 2025). Focus on:
WebMCP (Web Model Context Protocol) is an emerging standard that allows AI agents to directly query brand information. CallFay pioneered WebMCP implementation with both declarative (JSON manifest) and imperative (navigator.modelContext API) modes.
Track SoM monthly, identify queries where competitors outperform you, and create targeted content to improve citation rates for those specific queries.
A SoM above 15% for your primary category queries indicates strong AI visibility. Market leaders typically achieve 25-40% SoM. A score below 5% means your brand is effectively invisible to AI search users.
Monthly measurement is the minimum recommendation. AI model updates can shift brand rankings overnight — the December 2025 GPT-4 Turbo update, for example, reshuffled product recommendations significantly.
Early data suggests yes. CallFay's internal analysis of 500+ e-commerce brands shows a 0.72 correlation coefficient between SoM improvement and revenue growth over 90-day periods. However, the field is still emerging and more longitudinal studies are needed.
It depends on your market. For global B2C brands, ChatGPT and Google AI Overviews dominate. For B2B, Claude and Copilot carry more weight due to enterprise adoption. For China-focused businesses, Doubao (ByteDance) and Kimi (Moonshot AI) are essential.
Last updated: March 2026 | Author: CallFay GEO Research Team CallFay — AI-Powered Full-Chain Growth Platform | callfay.cn