The First Citation Index
A quarterly benchmark measuring how frequently AI models cite and recommend brands across industries. Based on 48,000+ queries tested across ChatGPT, Perplexity, Gemini, and Claude.
Published March 2026 · Sheltron Research Division
What is the Citation Index?
The First Citation Index is a quarterly research report that systematically measures how AI-powered search engines and assistants cite brands in their responses. Unlike traditional search rankings, AI citation is fundamentally different: there are no “ten blue links.” Instead, AI models generate natural language responses that either mention a brand or do not.
Each quarter, we generate thousands of realistic user queries across multiple intent categories — informational, commercial, navigational, and transactional — and submit them to four major AI models. We then analyze the responses to determine which brands are cited, how they are described, and what content attributes correlate with citation probability.
The Q1 2026 edition covers 14 industries, 48,000+ queries, and tracks over 2,400 brands. This is the third edition of the index, allowing us to identify meaningful quarter-over-quarter trends for the first time.
Key findings
Q1 2026 at a Glance
Average brand citation rate across all industries
+4.2% from Q4 2025
Citation advantage of structured content over unstructured
Consistent across models
Brands cited by all four major AI models
Down from 14% in Q4
Average citation half-life before freshness decay
Up from 39 days in Q4
Queries where AI recommends at least one brand
+9% from Q4 2025
Industry breakdown
Citation Rates by Industry
Percentage of queries where at least one brand in the industry was cited by AI models, averaged across all four models tested.
| Industry | Citation Rate | QoQ Change | Top Cited Brands |
|---|---|---|---|
| SaaS / Technology | 34.2% | +3.1% | Notion, Slack, Linear |
| Education | 31.0% | +2.8% | Coursera, Khan Academy, Duolingo |
| Finance & Banking | 28.4% | +1.9% | Wise, Stripe, Revolut |
| Healthcare | 22.1% | +4.7% | Mayo Clinic, WebMD, Healthline |
| E-commerce | 19.8% | +1.4% | Amazon, Shopify, Etsy |
| Media & Publishing | 18.3% | +2.2% | Reuters, AP News, The Verge |
| Travel & Hospitality | 16.5% | +1.1% | Booking.com, TripAdvisor, Airbnb |
| Real Estate | 14.7% | +0.8% | Zillow, Redfin, Realtor.com |
| Automotive | 13.2% | +1.5% | Edmunds, CarGurus, KBB |
| Legal Services | 11.9% | +2.1% | LegalZoom, Avvo, FindLaw |
Methodology
How We Measured
Queries were generated using a stratified sampling approach across four intent categories. Each query was submitted to ChatGPT (GPT-4o), Perplexity (Pro), Google Gemini (1.5 Pro), and Claude (Opus) via their respective APIs. Responses were parsed using a custom NER pipeline to extract brand mentions, then classified as direct citations, indirect references, or comparative mentions.
Citation rates represent the percentage of queries in which at least one brand in the industry was directly cited. All statistical comparisons use a 95% confidence interval with Bonferroni correction for multiple testing.
Download the Full Report
Get the complete Q1 2026 Citation Index with detailed brand-level data, model comparison charts, and methodology appendix.
48 pages · PDF · Free for non-commercial use
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