Analysis

How AI Recommendations Actually Work

What a study of the recommendation logic of ChatGPT, Gemini, Perplexity, and Claude shows

A machine turns search results, backlinks, and technical signals into recommendations in ChatGPT, Gemini, Perplexity, and Claude.

When a customer asks ChatGPT, “Where can I buy sustainable outdoor clothing online?”, the AI doesn’t simply return a random list. Behind the answer is a measurable system that weighs certain factors more heavily than others. This article explains how the four most relevant AI chatbots actually make recommendations—and what that means for German companies that want to become visible in these systems.

The foundation of this article is the most comprehensive empirical study of this topic to date: research by First Page Sage, a US-based GEO agency, which ran 11,128 commercial queries across the four largest AI chatbots between December 2023 and April 2026. Wherever specific figures or weightings are cited, we link back to the original research.

The AI Chatbot Market

Before diving into the individual algorithms, it is worth looking at market share.

Market Share of the Four Most Important AI Chatbots

US market, 2026

ChatGPT
61.3%
Google Gemini
13.3%
Perplexity
3.1%
Claude AI
2.5%

Data source: First Page Sage, 2026 market share study. Visualization: auffindbar.ai. No reliable comparable figures are currently available for the German market; based on our observations, ChatGPT is similarly dominant here.

The Eight Factors That Shape AI Recommendations

Across all four platforms, the First Page Sage study identifies eight factors that influence recommendation decisions. The weighting differs significantly between platforms. Six of these correspond directly to the six levers in our approach.

Authoritative List Mentions

AI chatbots primarily draw recommendations from highly ranked list-based articles that perform well in Google or Bing: comparative articles with tables, rather than traditional listicles.

Awards, Accreditations and Affiliations

When an award or certification is mentioned on a trusted website, it strengthens perceived authority.

Online Reviews

Reviews on Amazon, Trustpilot, the Better Business Bureau, Capterra, and other platforms. Below 3.5 stars, Gemini in particular consistently excludes a company from recommendations.

Social Sentiment

Perception in news articles, public social media discussions, and forums such as Reddit. Currently, only ChatGPT actively uses this factor.

Google Website Authority

The authority score calculated by Google, based on consistent publishing and backlinks from authoritative domains. Gemini gives this factor particularly strong weight.

Traditional Databases and Directories

Wikipedia, Encyclopedia Britannica, The New York Times, The Wall Street Journal, as well as business databases such as Hoovers, Bloomberg, and IBISWorld.

Customer Examples and Usage Data

When well-known brands publicly use a product, AI systems can infer credibility from that association. Currently, ChatGPT and Claude use this factor.

Local Business Reviews

Reviews from Google Business Profiles, Yelp, TripAdvisor, and Angie's List. Gemini and Perplexity use separate algorithms for local queries.

Data source: First Page Sage, eight factors influencing recommendation decisions. Visualization: auffindbar.ai

How ChatGPT Makes Recommendations

With a 61.3% market share, ChatGPT is by far the most important platform. ChatGPT searches Bing for highly ranked lists, reviews, and directories, then combines the top results into a recommendation.

The ChatGPT Recommendation Algorithm

Weighting of factors for commercial queries, US market, 2026

Authoritative List Mentions Mentions in highly ranked lists
41%
Awards & Accreditations Awards and certifications
18%
Online Reviews Reviews on trusted platforms
16%
Customer Examples & Usage Data Customer examples and usage data
14%
Social Sentiment User sentiment across social sources
11%

How to read this: Out of 100 ChatGPT recommendations, 41 are attributed to list mentions, 18 to awards, 16 to reviews, 14 to customer examples, and 11 to social sentiment.

Data source: First Page Sage, a US-based GEO agency; 11,128 commercial queries across the four largest AI chatbots, as of April 2026, US market. The underlying patterns are likely transferable to the German-speaking market. Visualization: auffindbar.ai.

For German companies, the implication is clear: the most important lever for ChatGPT visibility is presence in highly ranked comparison lists. In Germany, these include editorial lists from etailment, iBusiness, Testberichte.de, Stiftung Warentest, specialist publications such as TextilWirtschaft or Lebensmittel Zeitung, and consumer advice portals such as Computer Bild and CHIP.

How Google Gemini Makes Recommendations

Gemini actively distinguishes between general recommendation queries and local searches, and looks for providers that appear consistently across multiple top-ranked lists. Companies with online ratings below 3.5 stars are not recommended. This is an absolute exclusion criterion, not a gradual ranking signal.

The Gemini Recommendation Algorithm

Different weighting for general and local queries, 2026

General Queries

Authoritative List Mentions 49%
Google Website Authority 23%
Awards & Accreditations 15%
Online Reviews 13%

Local Queries

Local Business Reviews 38%
Authoritative List Mentions 29%
Online Reviews 19%
Google Business Profile Authority 14%

Data source: First Page Sage, a US-based GEO agency; Algorithm Breakdown, April 2026; 11,128 commercial queries across the four largest AI chatbots, US market. The underlying patterns are likely transferable to the German-speaking market. Visualization: auffindbar.ai.

How Perplexity Makes Recommendations

Perplexity has the leanest algorithm of the four: lists and reviews are almost the only relevant factors. That makes optimization clearer on the one hand, but the competitive landscape tougher on the other.

The Perplexity Recommendation Algorithm

The simplest of the four algorithms studied, 2026

General Queries

Authoritative List Mentions 64%
Online Reviews 31%
Awards & Accreditations 5%

Local Queries

Local Business Reviews 39%
Authoritative List Mentions 34%
Online Reviews 27%

Data source: First Page Sage, a US-based GEO agency; Algorithm Breakdown, April 2026; 11,128 commercial queries across the four largest AI chatbots, US market. The underlying patterns are likely transferable to the German-speaking market. Visualization: auffindbar.ai.

How Claude AI Makes Recommendations

Claude is the outlier among the four platforms. Claude has limited internet access and relies primarily on traditional databases. Local recommendations are systematically not offered, while established brands are structurally favored.

The Claude Recommendation Algorithm

The outlier among the four platforms, 2026

Traditional Databases & Directories Business databases, Wikipedia, encyclopedias
68%
Awards & Accreditations Awards and certifications
19%
Customer Examples & Usage Data Customer examples and usage data
13%

Data source: First Page Sage, a US-based GEO agency; Algorithm Breakdown, April 2026; 11,128 commercial queries across the four largest AI chatbots, US market. The underlying patterns are likely transferable to the German-speaking market. Visualization: auffindbar.ai.

The Patterns Across Platforms

Platform List MentionsAwardsReviewsSocial SentimentCustomer ExamplesGoogle AuthorityLocal ReviewsDatabases
ChatGPT 61.3% market share 41%18%16%11%14%
Gemini 13.3% market share, general 49%15%13%23%
Perplexity 3.1% market share, general 64%5%31%
Claude AI 2.5% market share 19%13%68%

Data source: First Page Sage, Algorithm Breakdown 2026. Visualization: auffindbar.ai. For Gemini and Perplexity, the weightings shown are for general queries.

First: List articles are the dominant factor. For ChatGPT, Gemini, and Perplexity, authoritative lists account for between 41% and 64% of the recommendation algorithm.

Second: Online reviews are a prerequisite, not a lever. Weak reviews below 3.5 stars can lead to exclusion, while above-average ratings do not measurably increase the probability of being recommended.

Third: SEO and GEO are interconnected, not separate. Anyone claiming that GEO replaces SEO has misunderstood the mechanism.

Fourth: Platforms are becoming increasingly personalized. The underlying logic remains, while personalization operates within the frameworks set by the algorithms.

The Implications

  1. Build a presence in highly ranked German comparison lists. Start with the biggest lever: identify relevant list articles, systematically approach editorial teams, and build your own comparative content that ranks in Google.
  2. Maintain review hygiene. Keep at least 3.5 stars on the relevant platforms. Not a lever, but the foundation.
  3. Keep your SEO fundamentals strong—or build them. Website authority, content quality, and technical performance.
  4. Publish reputation signals. Awards, certifications, press coverage, and industry memberships.
  5. If you have a local component, maintain your Google Business Profile. A separate lever for Gemini and Perplexity.
  6. Prioritize Claude optimization only for larger providers. With a limited budget, make it a later-stage priority.
The order follows the staircase: lists form the broadest and most important foundation.

This is exactly the work we do, from list and database outreach to reputation building. The first step is always measurement: the AI Visibility Analysis.

What These Findings Do Not Tell You

Algorithm weightings are not fixed. Platform operators regularly change how their systems work. The data is based on US queries, so the underlying patterns are likely transferable to the German market, but the specific weightings may differ. Reliable comparative figures for the German-speaking market are not yet available. Platforms are becoming increasingly personalized, so we work with probabilities, not guarantees. With consistent implementation, initial measurable shifts are typically visible after eight to twelve weeks, while substantial positioning can take six to twelve months.

Summary

ChatGPT (61.3% market share) weights list presence at 41%; Gemini (13.3%) at 49%, plus Google authority at 23%; Perplexity (3.1%) at 64%; and Claude (2.5%) relies on databases for 68% of its recommendation weighting. The most important lever is presence in highly ranked comparison lists across German specialist publications and consumer advice portals.

Sources and Further Reading

Primary source: First Page Sage, “Generative Engine Optimization (GEO): Explanation and Algorithm Breakdown,” April 2026 · “GEO Strategy Guide” · “Generative AI Chatbots by Market Share” · Gemini Team, Google (December 2023) · OpenAI, GPT-4 Technical Report (March 2023) · Sharma, Liao, Xiao (February 2024). All visualizations are original representations based on First Page Sage research data.

About the Author

Dennis Doerfl is Co-Founder and CEO. Learn more about the team.

How we start working together

The first step is always measurement.

Knowing where you stand is the first step. The AI visibility assessment measures your current visibility and gives you the numbers to back it up.

€590
one-time, net · fully credited toward a retainer booked within 60 days