How to Find Which Sources AI Engines Use

When ChatGPT answers a question about your industry, it doesn't make things up (most of the time). It retrieves specific web pages, evaluates them, and synthesizes a response. The pages it chooses to cite are not random. They follow patterns that have been studied across hundreds of millions of AI responses.

Understanding which sources AI engines prefer — and how those preferences vary by platform — gives you a concrete roadmap for where to invest your GEO efforts. This guide breaks down the data from the largest citation studies available and shows you how to identify the specific sources that matter for your niche.

The Big Picture: What 250K+ Citations Reveal

Several major studies have analyzed AI citation patterns at scale. Ahrefs examined 78.6 million AI interactions. Profound tracked 680 million citations. xFunnel analyzed 250,000 citations across 40,000 AI responses. The findings are remarkably consistent.

Here's what the data shows:

Wikipedia dominates across all platforms. It's ChatGPT's most-cited source at 16.3% of mentions, Perplexity's at 12.5%, and AI Overviews' at 8.4%. If your brand qualifies for a Wikipedia page, this is one of the strongest entity signals you can build.

YouTube is a top source — except on ChatGPT. Perplexity cites YouTube at 16.1% and AI Overviews at 9.5%, but ChatGPT largely ignores video content because it's not built to parse video natively. This has direct implications for your content format strategy.

Reddit is everywhere. Reddit appears in 68% of AI search responses across platforms. It's Perplexity's top non-reference source and accounts for 21% of Google AI Overview citations. AI engines trust Reddit because it provides authentic user experiences and community-vetted recommendations.

Only 12% of cited sources overlap across platforms. A source that ChatGPT cites is very likely not cited by Perplexity for the same query. Each platform has distinct retrieval logic and source preferences, making platform-specific monitoring essential.

Source Preferences by Platform

Each AI platform has distinct source preferences shaped by its search backend, retrieval architecture, and design philosophy. Here's what the research reveals.

The variance is striking. ChatGPT's Wikipedia reliance (16.3%) is almost double that of AI Overviews (8.4%). Perplexity's YouTube preference (16.1%) doesn't even register in ChatGPT's top sources. Reddit dominates AI Overviews at 7.4% but is a minor source for ChatGPT at 1.8%.

This means a single-platform GEO strategy will miss 88% of the citation landscape. Clairon tracks source citations across all these platforms simultaneously, showing you which specific sources AI engines pull from for each of your target queries — not industry averages, but your actual competitive landscape.

Which Source Categories Get Cited Most

Beyond specific domains, sources fall into categories that reveal how AI engines build trust and construct answers.

Earned Media (Most Cited Category)

Third-party editorial, affiliate, and press sources are the most frequent citation type across all platforms, according to xFunnel's analysis of 250,000 citations. This includes industry publications, news outlets, analyst reports, and review sites. AI engines prefer earned media because it represents independent validation — someone other than the brand itself vouching for the information.

Government sources are 11.75x more likely to be cited than average. Ecommerce pages are 5.10x. News/media sources are 2.56x. These multipliers show how dramatically source type affects citation probability.

User-Generated Content (UGC)

Reddit, Quora, G2 reviews, and community forums form the second-most-influential category. UGC appears in AI responses because it provides authentic user experiences that AI engines struggle to find elsewhere. G2 is the most-cited software review platform across ChatGPT, Perplexity, and AI Overviews.

The UGC category matters most for consideration-stage queries. xFunnel's research shows a noticeable increase in UGC citations during the solution comparison stage, as AI engines recognize that buyers want peer reviews and firsthand experiences at this point in their journey.

Owned Content

A brand's own website and content. Owned content matters most at the bottom of the funnel — when users ask specific questions about pricing, features, or implementation. AI engines cite first-party product pages, documentation, and case studies when users need specific details that only the brand can provide.

Reference Sources

Wikipedia, Wikidata, and knowledge bases. These are foundational to entity definition. Wikidata serves as the #1 source for Google's Knowledge Graph, containing 500 billion facts about 5 billion entities. If your brand doesn't have a clear, consistent entity presence in these reference sources, AI engines may not even understand who you are well enough to cite you.

Sources Change by Funnel Stage

One of the most actionable findings from large-scale citation research is that AI engines cite different source types depending on where the user is in their buyer journey. xFunnel's analysis breaks this down clearly.

This has a direct strategic implication: the type of source you need to be present on depends on which stage of the buyer journey you're targeting. If you want visibility during early research, earned media is your priority. If you want to influence the comparison stage, you need strong presence on review platforms and in community discussions. If you want to win the final decision, your own product pages need to be structured for AI extraction.

In Clairon, you can organize your prompt library by funnel stage and see which sources AI cites at each stage for your specific category. This tells you exactly where to invest at each point in the journey.

How to Find the Sources That Matter for Your Niche

Industry-level data gives you the big picture, but your GEO strategy needs niche-specific intelligence. The sources AI cites for "best CRM software" are completely different from the sources it cites for "best dental imaging technology." Here's how to find yours.

Step 1: Run Your Niche Through Clairon

Add 20-30 prompts covering your specific category, use cases, and buyer questions. Clairon runs them across ChatGPT, Perplexity, Gemini, Claude, Grok, and AI Overviews, capturing every source URL cited in each response. After a full monitoring cycle, you'll have a complete map of which sources AI trusts for your niche.

Step 2: Identify Your Category's Authority Sources

From Clairon's source data, identify the sources that appear most frequently across your target prompts. These are your category's "authority anchors" — the sites that AI engines default to when answering questions in your space. They might be a specific G2 category page, an industry blog, a Reddit subreddit, or a particular publication.

Sort by cross-platform presence (sources cited by multiple AI engines are the highest value) and by prompt breadth (sources cited across many different queries are foundational).

Step 3: Map Source Influence by Funnel Stage

Organize your findings by buyer journey stage. Which sources does AI cite for awareness queries vs comparison queries vs decision queries? This map tells you where to focus at each stage. If Reddit dominates your category's comparison queries but you have zero Reddit presence, that's a clear gap with a clear action.

Step 4: Check Your Presence on Each Source

For every high-influence source Clairon identifies, check: does this source mention or feature your brand? If it's a G2 category page, are you listed? If it's a "Best X" article, are you included? If it's a Reddit thread, is your product discussed? The sources where you're absent are your priority targets.

Step 5: Monitor Source Changes Over Time

The sources AI trusts aren't static. New publications emerge, existing pages get updated, community discussions evolve. Clairon's ongoing monitoring catches when new sources enter the citation landscape for your queries, so you can respond before competitors do. 40-60% of cited domains change monthly — so the source map you build today will need continuous updating.

How to Get Featured on High-Influence Sources

Once you've identified the sources that matter, here's how to earn presence on each type.

Review Platforms (G2, Capterra, TrustRadius)

G2 is the most-cited software review platform across all AI engines. If you're in SaaS and you're not on G2 with a strong profile, you're leaving AI citations on the table. Claim your profile, fill it completely, and actively solicit reviews from happy customers. Respond to reviews (positive and negative). Keep your feature descriptions and pricing current. The more complete and active your profile, the more likely AI will cite it.

Reddit

Reddit appears in 68% of AI responses. But you can't game Reddit. Promotional posts get downvoted and deleted. Instead: identify the subreddits where your category gets discussed, participate with genuinely helpful answers, build karma over months, and only mention your product when it's directly relevant to someone's question. Authentic engagement compounds over time — when AI eventually cites a Reddit thread recommending your product, that citation carries immense trust weight.

Wikipedia and Wikidata

If your company meets Wikipedia's notability requirements, pursue a page. If you can't get a full page, at minimum ensure your Wikidata entry is accurate: label, description, aliases, industry, founded date, headquarters, website, and social profiles. Wikidata feeds Google's Knowledge Graph, which feeds AI engines. Inaccurate or missing Wikidata creates entity confusion that hurts your citations everywhere.

Industry Publications

Earned media is the most-cited source category overall. Develop relationships with journalists and editors covering your space. Offer expert commentary, share proprietary data, and pitch thought leadership pieces. Focus on the specific publications Clairon shows you AI cites for your category — not just high-DR sites in general, but the exact publications that appear in your target AI responses.

"Best of" and Comparison Lists

Listicles like "Best [Category] Tools 2026" are citation magnets because they answer comparison queries directly. Identify the lists that AI cites for your category (Clairon's source data shows you exactly which ones). Reach out to be included. If key lists don't include you, create your own authoritative comparison content that positions you in the conversation.

Your Own Website

For bottom-of-funnel queries, AI engines do cite owned content — especially product pages, pricing pages, and documentation. Ensure these pages are structured for AI extraction: front-loaded answers, clear headers, specific data points, and proper schema markup. Don't forget to make your site AI-crawlable.

Continue with the source and citation series:

How to Get Cited by AI Search Engines
Domain Authority vs AI Citation Authority
Competitor Citation Analysis: Find Their Sources
How Do AI Search Engines Work?
Entity Optimization Guide for GEO
How to Do GEO: Complete Implementation Guide