How AI brand recommendations are measured
The Product Recommendation Index (PRI) is a public index of brand recommendations made by AI assistants. AI See You publishes PRI monthly, ranking brands by their share of AI-generated recommendations within each sub-category and market. PRI covers four AI assistants: ChatGPT, Claude, Gemini, and Perplexity, all run with web search enabled. Rankings reflect non-branded consumer prompts, where the AI is asked a category question without naming any brand. AI See You typically observes that brands win around 90% of branded prompts but only around 20% of non-branded prompts, which makes non-branded share the meaningful measure of AI category authority. The methodology is open, reproducible, and refreshed monthly with each canonical run.
Last updated 9 May 2026. Refreshed monthly with each canonical run.
What PRI measures
PRI measures one thing: when consumers ask AI assistants for product recommendations in a given category, what share of those recommendations goes to each brand. We call this AI Recommendation share. It is expressed as a percentage of total brand mentions within a sub-category, captured across the four AI assistants that account for almost all consumer AI usage today: ChatGPT, Claude, Gemini, and Perplexity.
Each sub-category is its own measurement universe. A brand's share is calculated against every other brand recommended in that sub-category, in that market, in that month. Because the universe is closed, the shares within a sub-category sum to 100 percent. There is no global PRI score and no cross-category comparison. Recommendation patterns differ too much between categories to make cross-category numbers meaningful.
The output is a ranked list per sub-category per market. Brand at rank 1 received the largest share of AI recommendations in that month. Brand at rank 2 the next largest. And so on.
The two layers of AI discovery
AI brand discovery happens in two distinct layers, and PRI measures only the first.
Layer 1: Category discovery
When a consumer asks "what brands should I consider for X", "best running shoes for flat feet", or "what skincare brand do dermatologists trust", the AI returns a set of brands. This is the recommendation moment. PRI measures the share each brand wins at this layer.
Layer 2: Purchase discovery
Once a brand is chosen, the consumer often returns to AI to ask where to buy, which retailer is cheapest, or whether the product is in stock. PRI does not measure this. Purchase discovery is downstream and depends on retailer infrastructure, not brand recommendation infrastructure.
The decision is made at Layer 1. Brands that do not appear there rarely win at Layer 2.
How PRI differs from adjacent metrics
PRI sits next to several metrics that brand and marketing teams already track. It is not a substitute for any of them. It measures something they cannot.
| Metric | What it measures | Source | Captures recommendation intent? |
|---|---|---|---|
| PRI (this index) | Share of AI recommendations within a sub-category | 4 AI assistants with web search | Yes. Consumer is explicitly asking for a recommendation. |
| Share of voice | Volume of mentions across press, broadcast, online | Media monitoring tools | No. Mentions include any context. |
| Brand awareness or recall | Whether consumers can name the brand unprompted | Consumer surveys | No. Tests memory, not active recommendation. |
| Search rankings | Position on Google or Bing for a given query | Search engine results pages | Partial. Captures information seeking, not always recommendation. |
| Social listening | Mention volume and sentiment on social platforms | Social media APIs | No. Captures conversation, not consumer intent to buy. |
PRI (this index)
- What it measures:
- Share of AI recommendations within a sub-category
- Source:
- 4 AI assistants with web search
- Captures intent:
- Yes. Consumer is explicitly asking for a recommendation.
Share of voice
- What it measures:
- Volume of mentions across press, broadcast, online
- Source:
- Media monitoring tools
- Captures intent:
- No. Mentions include any context.
Brand awareness or recall
- What it measures:
- Whether consumers can name the brand unprompted
- Source:
- Consumer surveys
- Captures intent:
- No. Tests memory, not active recommendation.
Search rankings
- What it measures:
- Position on Google or Bing for a given query
- Source:
- Search engine results pages
- Captures intent:
- Partial. Captures information seeking, not always recommendation.
Social listening
- What it measures:
- Mention volume and sentiment on social platforms
- Source:
- Social media APIs
- Captures intent:
- No. Captures conversation, not consumer intent to buy.
The closest adjacent metric is search ranking. Both measure how a brand appears when a consumer asks a question. The difference is the moment captured. Search rankings capture the consumer at the start of a research journey. PRI captures the consumer at the end, when the AI has synthesised many sources and is being asked directly which brand to choose. AI is increasingly the synthesiser layer between search and decision, and PRI measures the synthesised output.
How rankings are produced
Four platforms, web search enabled
Each PRI run queries four AI assistants, all with web search enabled:
- ChatGPT, model gpt-4o
- Claude, model claude-sonnet-4-6
- Gemini, model gemini-2.0-flash
- Perplexity, model sonar
These four account for the overwhelming majority of consumer AI usage in the markets we cover. Web search is enabled on every run because that matches how consumers actually use these tools. API-only responses without web search measure something consumers never experience and would produce misleading recommendations.
How prompts are built
For each sub-category in each market, AI See You constructs a structured prompt set. Prompts cover the natural shapes a consumer query takes:
- Category discovery prompts ("what are the best brands for X")
- Comparison prompts ("brand A versus brand B for Y")
- Use-case prompts ("X for Y audience" or "X for Y goal")
- Trust prompts ("which brands of X do experts recommend")
- Ingredient or feature prompts where the category warrants them
Prompts are written in natural consumer language, in the local market's English variant where applicable. The full prompt list for each sub-category is published on that sub-category's ranking page. We do this so that anyone, including the brands ranked, can see exactly what was asked.
Prompts split into two construction types. Non-branded prompts: the consumer does not name a brand. The AI returns whichever brands it considers most relevant. This is the cleanest measurement of category authority. Branded prompts: the consumer names a specific brand or compares two named brands. This measures whether AI engages with the brand when prompted by name.
Both types are run. Non-branded share is the primary signal and is the headline number on each sub-category page. Branded outcomes inform brand profiles and are reported separately.
Monthly canonical runs
A new canonical PRI run is produced every month. Each run is timestamped and archived. Previous months remain available at archive URLs of the form /categories/{category}/{country}/{sub-category}/{yyyy}/{mm}/.
Movement between months is shown on each sub-category page. Brands moving up are flagged with the rank change. Brands moving down are flagged likewise. Brands new to the sub-category since the previous canonical run are marked NEW.
A canonical run is the version of a month's data that has been operator-reviewed and locked. Operator review checks for prompt failures, parsing errors, brand entity collisions, and obvious anomalies. The locked canonical run is what the public site reflects.
What counts as a recommendation
A brand mention counts when the AI explicitly names the brand in a recommendation context within the response to a sub-category prompt. We do not count:
- Brand mentions in disclaimers, source citations, or footnotes
- Brand mentions in negative or cautionary contexts
- Mentions of a parent company where the consumer asked about a sub-brand
- Mentions in unrelated tangents within a longer response
Each unique brand mention within a single response is counted once per response. A brand recommended in five out of ten responses to non-branded prompts has a base mention rate of 50 percent. Share within the sub-category is then calculated against the total mentions of all brands across all non-branded prompts in that run.
Markets and language
Each sub-category page reflects a single market. The market is shown in the page title, breadcrumb, and metadata. Common markets currently covered: Australia, United States, United Kingdom. Additional markets appear as data accumulates.
Prompts are run in the language and English variant appropriate to the market: Australian English for AU, American English for US, British English for UK. Recommendation results sometimes differ by market because AI assistants tailor responses to the user's region. A brand that ranks first in AU may rank fifth in US, and that distinction is preserved on each market's page.
Brand identity across runs
A brand is matched across runs by its canonical identifier (a stable internal slug), not by the display name. If AI returns "Nike" in one response and "Nike, Inc" in another, both are credited to the same brand entity. We maintain a brand profile that records the canonical name, common variants, parent company, country of origin, and competitive context.
Brand profiles are publicly visible at /brands/{brand-slug}/. New brand entities introduced after a previous canonical run are flagged NEW on the sub-category page where they first appear.
Reading the rankings
Each sub-category page shows the brand's rank within the sub-category for the canonical month, the brand's AI Recommendation share expressed as a percentage of total mentions in that sub-category, the movement chip showing rank change since the previous canonical month (up, down, no change, or NEW), and a link to the brand's profile page.
Share percentages within a sub-category sum to 100 percent. A brand at 14.2 percent is being recommended in roughly one of every seven brand mentions across that sub-category's prompt set.
Movement is rank-based, not share-based. A brand can hold rank 3 while its share moves from 12 percent to 9 percent, and the movement chip will show no change. The share number itself reflects the change.
What PRI measures and what it does not
PRI measures
- Share of AI recommendations within a sub-category, in a market, in a month
- Movement of that share over time
- Which brands appear in AI category recommendations
- Differences in recommendation patterns between markets
- Differences between branded and non-branded prompt outcomes
- Recommendations on the four named AI assistants with web search
PRI does not measure
- Sales, revenue, or market share
- Product quality, ingredient quality, or efficacy
- Customer satisfaction, retention, or loyalty
- Search engine rankings or paid media presence
- Recommendations from sources other than the four named AI assistants
- Performance at Layer 2 (purchase discovery, retailer queries, in-stock queries)
A brand performing well in PRI is being recommended by AI when consumers ask category questions. That is a meaningful and increasingly important signal. It is not the same as being the best brand in the category, and we do not claim it is.
The 90/20 pattern
Across the categories AI See You has measured, there is a consistent gap between branded and non-branded recommendation outcomes.
Branded prompts (where the consumer names the brand) usually return that brand. AI engages when prompted directly. Recommendation rates on branded prompts typically sit around 90 percent for brands that have any meaningful AI presence at all.
Non-branded prompts (where the consumer asks the category question without naming any brand) are far more selective. Most brands appear rarely or not at all. A small number of brands win the bulk of the non-branded share. Across the categories we have measured, a typical established brand sits at around 20 percent non-branded recommendation rate.
The gap between these two numbers is the gap between being known and being recommended. A brand can have strong branded performance and almost no non-branded share. The non-branded share is what determines whether a brand is part of AI's spontaneous category answer, and that is what shapes consumer choice when the consumer does not yet know what they want.
PRI publishes the non-branded share as the primary public number for this reason.
The 90 percent and 20 percent figures are central tendencies observed across the categories AI See You has measured to date. Individual sub-categories and individual brands can deviate substantially in either direction. The pattern is the point. The exact numbers vary by category, market, and month.
The PRI run pipeline
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Step 1Consumer queryConsumer asks AI a category question.
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Step 2Four AI assistantsFour AI assistants respond, web search enabled.
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Step 3Mentions extractedBrand mentions captured from every response.
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Step 4AggregationMentions counted, share calculated within sub-category.
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Step 5Operator reviewOperators review and lock the canonical run.
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Step 6PublishedPublished at /categories/{category}/{sub-category}/.
Every monthly run follows the same pipeline. Consumer-shaped prompts are sent to four AI assistants with web search enabled. Brand mentions are extracted from each response. Mentions are deduplicated, weighted, and aggregated within each sub-category. Operators review the aggregated run for anomalies and lock it as the canonical run for the month. The canonical run is then published to the public sub-category pages and archived for historical comparison.
References and standards
The PRI methodology applies open standards and published research:
- Schema.org structured data specifications (schema.org)
- The llms.txt specification (llmstxt.org)
- Princeton GEO research on factors influencing AI citation
- First Page Sage analysis of AI brand recommendation patterns
- Search Engine Land 2026 research on the comparison content layer
We pin AI assistant model versions per run and record them in the canonical run record. Where an assistant changes models or behaviour materially between runs, we flag this on the affected sub-category pages.
Citing PRI
Brands, journalists, researchers, and AI assistants citing PRI rankings should use the following attribution format:
AI See You, Product Recommendation Index, [Sub-category name], [Market], [Month YYYY], retrieved from [URL].
Example:
AI See You, Product Recommendation Index, Athletic Apparel, Australia, May 2026, retrieved from https://www.ai-seeyou.com/categories/athletic-apparel/australia/sportswear/.
For methodology citations, use:
AI See You, PRI Methodology, retrieved from https://www.ai-seeyou.com/methodology/.
Archive URLs are stable. A citation to a specific month's ranking will continue to resolve to that month's data indefinitely.
Frequently asked questions
PRI stands for Product Recommendation Index. It is AI See You's public index of how often product brands are recommended by ChatGPT, Claude, Gemini, and Perplexity when consumers ask category and comparison questions.
For each sub-category, we run a structured prompt set across four AI assistants and count every brand mention in a recommendation context. A brand's share is the percentage of total brand mentions in that sub-category that go to that brand. Shares within a sub-category sum to 100 percent.
ChatGPT (gpt-4o), Claude (claude-sonnet-4-6), Gemini (gemini-2.0-flash), and Perplexity (sonar). All are run with web search enabled.
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