AI Research Tools

Our top three AI research tools

These three do different jobs more than they compete. Elicit comes first for finding papers: its free plan has no cap on search, summaries or chat with papers. ChatPDF is second for asking questions of a document you already have. Semantic Scholar is third as the search engine with nothing to pay. Consensus narrowly missed: its free tier stops at 10 Pro messages and 3 Deep Searches a month, and its paid prices could not be confirmed. Anara answers across a whole library of files but has no Windows or Android app. ResearchRabbit maps how papers connect, free with unlimited searches.

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   First: Elicit

   Free plan · from $49/mo

   For: Most people looking for papers on a research question

   Elicit searches more than 138 million academic papers from a research question, not exact keywords. Its free Basic plan includes unlimited search, unlimited paper summaries and chat with papers, plus Zotero import. A Research Agent writes cited reports, and a separate workflow handles screening and data extraction for systematic reviews. Know the limits: it runs in a browser, with a Chrome extension and no phone or desktop app listed. Research Agent and report usage is limited on Basic, the systematic review workflow starts at Pro, at $49 per user a month billed annually, and the $11 academic Plus plan appears only when Academic is selected on the pricing page.

   Elicit pricing and details
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   Second: ChatPDF

   Free plan · from $89.99/yr

   For: Anyone with a document to question, not papers to find

   ChatPDF answers questions about a file you bring: a PDF, Word, PowerPoint, Markdown or text file, or a YouTube or website link, with the answer shown beside the source and clickable citations. The free plan covers 2 documents and 20 messages a day and works without an account, and it runs on the web, Mac, Windows, iPhone and Android. It is second because it reads what you give it more than it searches: its paper summaries are built from abstracts, and chatting with a full paper works only for open-access papers. Free files stop at 120 pages or 10 MB. Plus is $14.99 a month or $89.99 a year on the US App Store, and the website sets its own price per visitor.

   ChatPDF pricing and details
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   Third: Semantic Scholar

   Free

   For: Anyone who wants to pay nothing

   Semantic Scholar is a search engine for scientific papers that is entirely free, with no paid plans, built by the nonprofit Allen Institute for AI. It indexes more than 200 million papers from all fields of science, and a free account adds a library, email alerts and Research Feeds that recommend new papers. It is third because its AI does less than the two above: the short TLDR summaries cover only computer science, biology and medicine, the Semantic Reader is in beta and covers mostly arXiv papers, and Ask This Paper works on a limited set of papers. There is no smartphone app; the site is designed to be used in mobile browsers.

   Semantic Scholar pricing and details

Ranked on Oct 6, 2026 from what each listing shows and what people say about the tool, not from our own testing. How we rank