# OpenAI ChatGPT Citation Share - March 2026 The top 20 websites ChatGPT Search cited most in March 2026, ranked by share of all citations, with notes for SEO teams working on generative engine optimization (GEO). ## The Most Cited Domains on OpenAI ChatGPT in March 2026 Based on Promptwatch data from Feb 28 - Mar 30, 2026. Citations tracked from real prompt responses using ChatGPT Search when triggered in the UI. ### What this means for you March is a two-horse race at the top: Wikipedia takes 3.61% of all ChatGPT Search citations with Reddit right behind at 3.21%, a gap of just 0.4 points. Encyclopedic reference and community discussion are pulling nearly equal weight in ChatGPT's answers. The rest of the field sits below half a percent: TechRadar leads the chasing pack at 0.46%, followed by arXiv (0.34%), Forbes (0.33%), and Walmart (0.31%). Even summed, these 20 well-known domains capture only around a tenth of all citations; the long tail of specialized sites takes the rest. #### How to act on it - Cover both flanks: maintain accurate, well-cited Wikipedia content where your brand has notability, and earn authentic mentions in the subreddits your buyers frequent. In March, ChatGPT drew on both almost equally. - Take the niche categories seriously. arXiv (0.34%) and Walmart (0.31%) cracking the top six shows that original research and structured product data get cited. Publish primary data and keep product pages machine-readable. - Aim your own content at specific, answerable questions. With ~90% of citations going past these 20 giants to smaller sites, precise factual pages on your domain can win the prompts that matter to your business. ## OpenAI ChatGPT Citation Share February vs March 2026 Side-by-side comparison of citation share for the top domains on ChatGPT Search between February and March 2026. ### What this means for you The gap at the top is closing: Reddit climbed from 2.96% in February to 3.21% in March while Wikipedia slipped from 3.8% to 3.61%, which cut Wikipedia's lead from 0.84 points to just 0.40. Further down, the movers are striking: arXiv more than doubled (0.14% to 0.34%), Walmart tripled (0.10% to 0.31%), and Business Insider doubled (0.08% to 0.16%), while LinkedIn (0.34% to 0.25%) and Trustpilot (0.23% to 0.16%) gave up ground. ChatGPT's sourcing mix is anything but static. #### How to act on it - Get ahead of the Reddit trend: it added a quarter point of share in one month, so start building genuine subreddit presence now rather than after the platform becomes even more dominant. - Copy what the risers have in common: primary sources. Publish original research or data (the arXiv playbook) and keep product and pricing information structured and current (the Walmart playbook). - Don't build your AI visibility on a single third-party platform. LinkedIn and Trustpilot both lost meaningful share this month; a spread across community, review, and owned channels survives these swings. ## How we collect this data We collect millions of prompt responses, citations, and click data from the actual user interfaces of major AI platforms: over 26 billion data points and growing. This gives us one of the largest datasets on how AI search engines cite sources and recommend brands. ### Real UI monitoring Data straight from the interfaces of ChatGPT, Gemini, Perplexity, Claude, AI Overviews, and more. ### 26B+ data points Over 26 billion analyzed citations, prompts, and responses, one of the largest AI search datasets available. ### Continuously updated Refreshed constantly so the trends you see reflect the latest behavior of AI search engines. ### Aggregated & public Published freely for the GEO community, based on aggregated, non-identifiable trends.