--- title: I made ChatGPT, Claude, and Gemini summarize a report... description: A hands-on test of ChatGPT, Claude, and Gemini summarizing a 47-page Reuters Institute report on journalism trends — one the author had already read in full.... canonical: https://daily.dev/posts/i-made-chatgpt-claude-and-gemini-summarize-a-report-i-d-actually-read-and-caught-all-three-making-sqw6lo1mh twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: I made ChatGPT, Claude, and Gemini summarize a report I'd actually read, and caught all three making things up | daily.dev og:description: A hands-on test of ChatGPT, Claude, and Gemini summarizing a 47-page Reuters Institute report on journalism trends — one the author had already read in full.... og:url: https://daily.dev/posts/i-made-chatgpt-claude-and-gemini-summarize-a-report-i-d-actually-read-and-caught-all-three-making-sqw6lo1mh og:image: https://api.daily.dev/og/posts/SqW6lO1MH.png og:image:alt: I made ChatGPT, Claude, and Gemini summarize a report I'd actually read, and caught all three making things up og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # I made ChatGPT, Claude, and Gemini summarize a report I'd actually read, and caught all three making things up **[XDA Developers](https://daily.dev/sources/xda-developers)** · 4 min read · 0 upvotes · 0 comments ## Summary A hands-on test of ChatGPT, Claude, and Gemini summarizing a 47-page Reuters Institute report on journalism trends — one the author had already read in full. All three models made factual errors, most of which involved misrepresenting what numbers actually measured rather than inventing statistics outright. Claude incorrectly characterized all report data as survey-based opinion, ignoring measured Chartbeat data. Gemini misclassified a self-reported survey finding as independently measured data. The author recommends using the strongest available model, giving it time to think, or switching to NotebookLM (now Gemini Notebook), which grounds responses strictly in uploaded sources. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Questions this post answers ### Do ChatGPT, Claude, and Gemini hallucinate when summarizing PDF documents? Yes, all three models produced factual errors when summarizing a 47-page Reuters Institute report. Claude incorrectly stated that every percentage in the report reflected executive opinion, ignoring measured Chartbeat data covering 2,576 websites. Gemini misclassified a self-reported survey result as independently measured data. ChatGPT listed sources and facts not present in the report at all. _Developers relying on AI for document analysis track reliability gaps like these on daily.dev._ ### Is NotebookLM more accurate than ChatGPT or Claude for summarizing uploaded documents? NotebookLM tends to produce fewer hallucinations for document summarization because its responses are grounded strictly in the sources you upload, making it less likely to introduce facts or citations not present in the original file. ChatGPT, Claude, and Gemini all introduced errors when summarizing the same PDF, including misattributed statistics and fabricated source references. _Teams choosing between AI summarization tools for research workflows find comparisons like this on daily.dev._ ## Similar posts on daily.dev - [I made ChatGPT, Claude, and Gemini summarize the same 200\+ page PDF, and the results weren't even close](https://daily.dev/posts/i-made-chatgpt-claude-and-gemini-summarize-the-same-200-page-pdf-and-the-results-weren-t-even-cl-wamalzvlq) · XDA Developers · 1 upvotes · 0 comments - [Why GPT-5.4, Claude, and Gemini can’t agree on basic, real-world facts](https://daily.dev/posts/why-gpt-5-4-claude-and-gemini-can-t-agree-on-basic-real-world-facts-q7pcokdcw) · The New Stack · 0 upvotes · 0 comments - [I gave ChatGPT, Claude, and NotebookLM the same 100-page PDF — here's who actually understood it](https://daily.dev/posts/i-gave-chatgpt-claude-and-notebooklm-the-same-100-page-pdf-here-s-who-actually-understood-it-ekoj6outd) · XDA Developers · 0 upvotes · 0 comments - [ChatGPT vs Gemini vs Claude: How They Differ](https://daily.dev/posts/chatgpt-vs-gemini-vs-claude-how-they-differ-du3af09ts) · ByteByteGo · 2 upvotes · 0 comments - [ChatGPT, Claude, Gemini and Grok are not ready to brief American voters](https://daily.dev/posts/chatgpt-claude-gemini-and-grok-are-not-ready-to-brief-american-voters-l5k5tlnyb) · The Next Web · 1 upvotes · 0 comments --- Tags: [#llm](https://daily.dev/tags/llm), [#chatgpt](https://daily.dev/tags/chatgpt), [#claude](https://daily.dev/tags/claude), [#notebooklm](https://daily.dev/tags/notebooklm) [View this post on daily.dev](https://daily.dev/posts/i-made-chatgpt-claude-and-gemini-summarize-a-report-i-d-actually-read-and-caught-all-three-making-sqw6lo1mh) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"I made ChatGPT, Claude, and Gemini summarize a report I'd actually read, and caught all three making things up","url":"https://daily.dev/posts/i-made-chatgpt-claude-and-gemini-summarize-a-report-i-d-actually-read-and-caught-all-three-making-sqw6lo1mh","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/i-made-chatgpt-claude-and-gemini-summarize-a-report-i-d-actually-read-and-caught-all-three-making-sqw6lo1mh"},"datePublished":"2026-08-11T10:02:50.650Z","dateModified":"2026-08-11T10:07:40.536Z","description":"A hands-on test of ChatGPT, Claude, and Gemini summarizing a 47-page Reuters Institute report on journalism trends — one the author had already read in full....","image":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/8f9c17b885e10ffc93556dcb5757e165?_a=AQAEuop","thumbnailUrl":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/8f9c17b885e10ffc93556dcb5757e165?_a=AQAEuop","isAccessibleForFree":true,"articleSection":"XDA Developers","inLanguage":"en","publisher":{"@type":"Organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180}},"author":{"@type":"Organization","name":"XDA Developers","logo":"https://media.daily.dev/image/upload/s--kCg6yyAP--/f_auto,q_auto/v1774964407/logos/xda-developers?_a=BAMAMiWQ0","url":"https://daily.dev/sources/xda-developers"},"commentCount":0,"discussionUrl":"https://daily.dev/posts/i-made-chatgpt-claude-and-gemini-summarize-a-report-i-d-actually-read-and-caught-all-three-making-sqw6lo1mh","interactionStatistic":[{"@type":"InteractionCounter","interactionType":{"@type":"LikeAction"},"userInteractionCount":0},{"@type":"InteractionCounter","interactionType":{"@type":"CommentAction"},"userInteractionCount":0}],"keywords":"llm,chatgpt,claude,notebooklm","timeRequired":"PT4M"} {"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https://daily.dev"},{"@type":"ListItem","position":2,"name":"XDA Developers","item":"https://daily.dev/sources/xda-developers"},{"@type":"ListItem","position":3,"name":"I made ChatGPT, Claude, and Gemini summarize a report I'd actually read, and caught all three making things up"}]} {"@context":"https://schema.org","@type":"FAQPage","@id":"https://daily.dev/posts/i-made-chatgpt-claude-and-gemini-summarize-a-report-i-d-actually-read-and-caught-all-three-making-sqw6lo1mh#faq","mainEntity":[{"@type":"Question","name":"Do ChatGPT, Claude, and Gemini hallucinate when summarizing PDF documents?","acceptedAnswer":{"@type":"Answer","text":"Yes, all three models produced factual errors when summarizing a 47-page Reuters Institute report. 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