# GeoXylia > Free AI citation checker: see what ChatGPT, Perplexity, Gemini and Claude need in order to quote your site, scored across nine dimensions with exact fixes. ## AI Citation Checker: See Which AI Models Actually Cite You See what ChatGPT, Perplexity, Gemini and Claude need in order to quote your site. A free audit scores your citation readiness across every major AI platform and says exactly what to fix. Check Your AI Citations - - Built on proven AI citation research 55+Engine Checks11Industries4AI Engines<60sAudit Time // HOW AI CITATIONS WORK ## AI models cite content differently than Google ranks it When you ask an AI model a question, it does not run a keyword search and return a ranked list. It retrieves relevant passages from its training data or live web sources, synthesizes them into an answer, and cites the sources that informed that answer. This retrieval-and-synthesis process is called RAG (Retrieval-Augmented Generation). Each platform uses its own RAG system: Perplexity favors multi-source synthesis (averaging 21.87 citations per response), ChatGPT leans on entity authority and FAQ schema, Gemini prioritizes factual density, and Claude looks for structured content with clear sourcing. The critical insight: only 11% of domains are cited by both ChatGPT and Perplexity. A site invisible on one platform may rank well on another. Checking all four models is the only way to understand your true AI visibility. Check Perplexity citations →Check ChatGPT visibility →Run a full GEO audit → // 6 FACTORS THAT DRIVE AI CITATIONS ## What determines whether AI models cite you ## Answer-first structure Lead every page with a direct answer to the question. AI models extract from the first 30% of content for 44.2% of citations across all platforms. ## Factual density Include specific numbers, dates, named entities, and cited sources. Models verify content against other sources and reward claims backed by data. ## Content recency Content published in the last 30 days is cited 2.1x more often than older content. Perplexity is the most recency-sensitive platform at 82% last-30-days citation rate. ## Schema markup FAQPage, Article, and HowTo schema help AI models understand content structure. Pages with FAQPage schema see 34% higher extraction rates in ChatGPT responses. ## llms.txt presence An llms.txt file tells AI crawlers which pages matter most, giving them an explicit map instead of leaving importance to be inferred from crawl structure. ## Entity clarity Clear brand signals (Wikipedia, Wikidata, LinkedIn) help models identify and trust your domain. Sites with verified Knowledge Graph entries cite 47% more often. // WHAT THE CHECKER REPORTS ## Per-model citation breakdown for every AI platform - Citation presence by platform Whether your site appears in each model's responses for queries relevant to your domain. Reported per model with citation count and frequency. - - Citation context and format How each model uses your content: direct quote, paraphrased attribution, or linked reference without naming your brand. Format varies significantly by platform. - - Competitor comparison Which competitors appear instead of you on each platform, and how often. The cross-platform competitor gap reveals where your content is weakest. - - Content gap analysis Specific queries where your content should be cited but is not, organized by platform. Each gap includes a recommendation for closing it. - - Cross-platform score Your aggregate AI Visibility Score across all 4 platforms (0-70 scale), benchmarked against 476 real audited sites. - GeoXylia scores your site against the retrieval signals each platform favours. No black box, and no one-off sample that changes between runs. Compare your score across all platforms or run a Perplexity-specific check. // PLATFORM COMPARISON ## ChatGPT, Perplexity, Gemini, and Claude each cite differently Only 11% of domains are cited by both ChatGPT and Perplexity. A site that ranks well on one platform can be invisible on another because each model uses different retrieval criteria. ChatGPT leans heavily on entity authority and FAQ schema. Pages with FAQPage schema see 34% higher extraction rates. Perplexity favors recency most aggressively (82% of citations from the last 30 days). Gemini prioritizes factual density and structured data. Claude rewards content with clear sourcing and verifiable claims. Checking one platform tells you almost nothing about your performance on the others. A comprehensive AI citation checker must cover all four to give you an accurate picture. Run a cross-platform audit →Start your free audit → // FAQ ## Frequently asked questions What is an AI citation checker? - - - - An AI citation checker scans your website across major AI platforms (ChatGPT, Perplexity, Gemini, Claude) to see if your content is referenced in their generated answers. GeoXylia's checker scores your site against the retrieval signals each platform favours - entity authority, answer-first structure, factual density, freshness and schema - and tells you which to fix first. I ## Links - [GXGeoXylia](/) - [Features](/features) - [Pricing](/pricing) - [Methodology](/methodology) - [Blog](/blog) - [FAQ](/faq) - [About](/about) - [Free Audit](/audit) - [Check Perplexity citations →](/perplexity-seo-checker) - [Check ChatGPT visibility →](/chatgpt-seo) - [Run a full GEO audit →](/geo-audit) - [Zhenliang Lim — Founder on LinkedIn](https://www.linkedin.com/in/zhenlianglim) - [GeoXylia audit tool — GitHub](https://github.com/Elzlxx) - [Follow GeoXylia on X](https://x.com/geoxylia) - [Case Studies](/case-studies) - [Contact](/contact) - [Dashboard](/login) - [GEO Fundamentals](/blog/geo-fundamentals) - [AI Citations](/blog/ai-citations) - [Perplexity](/blog/perplexity-seo) --- Generated by [GeoXylia](https://geoxylia.com) — AI Visibility Platform