10 Best AI PDF Chat Tools of 2026

Claude is a general AI assistant, but its document handling is what puts it first here. Anthropic's help center says chat uploads accept PDFs up to 1,000 pages and 500MB per file, with up to 20 files in one chat. On PDFs of 100 pages or fewer, Claude reads charts, images and graphics as well as the text, which matters for annual reports, research papers and slide decks where the numbers sit in figures. Files added to a Project stay available across conversations, so a team can keep a contract set or a course reader in one place. Pro costs $17 a month billed annually or $20 monthly, and the free plan also takes uploads. The limits are worth knowing: PDFs longer than 100 pages are read as text only, project files are capped at 30MB each, and free usage resets every 5 hours with a weekly cap. We compared documented features and published prices.

Google now calls NotebookLM Gemini Notebook, and it is still at notebooklm.google. It works differently from a single-file chat: you build a notebook of sources and every answer is grounded in what you added. The free plan allows up to 50 sources per notebook, which is enough for a semester of lecture notes and readings. For students, the study outputs are the draw. Google's pages describe turning class material into an Audio Overview to listen to recaps, generating Flashcards before an exam, and building Mind Maps to connect topics. Paid tiers raise limits rather than change the product: Google AI Plus at $4.99 a month in the US doubles usage and allows 100 sources per notebook, and Google AI Pro at $19.99 allows 300. The trade-off is that the paid plans are only sold in specific regions, and the notebook model takes a minute longer to set up than dropping one PDF into a chat. We compared documented features and published prices.

ChatGPT is the tool many students and office workers already have open, and its file uploads cover most PDF questions. OpenAI's help center says documents and presentations can be up to 512MB per file, text and document files are capped at 2 million tokens per file, and users can upload up to 80 files every 3 hours. Projects keep files together for repeat work: Free allows 5 files per project, Go and Plus allow 25, and Pro, Business and Enterprise allow 40. Uploads are available on the Free plan, which makes ChatGPT an easy first step for a one-off contract or a homework reading. The catch on the free tier is volume, since free users are limited to 3 file uploads per day. The paid plans are Go, Plus and Pro, but OpenAI's pricing page showed local currency from our location, so we list the USD price as pending. We compared documented features and published prices.

Humata prices by pages, which makes it easy to budget for a team that reads a known amount each month. The free plan includes 60 pages a month for one user. Expert costs $9.99 a month, covers up to three people and includes 500 pages, with extra pages at $0.02 each. Team costs $49 per user a month for up to 10 people and 5,000 pages, cuts extra pages to $0.01 and adds OCR, response personalization, and folder and department level permissions. Every plan lists GPT-5 support. The structure suits consultancies, small legal teams and research groups that share a document set. It suits individuals less well: 60 free pages is one long report, and scanned PDFs need OCR, which starts on the $49 Team plan. Security buyers should note that the SOC-2 certificate and uptime SLA are listed only on Enterprise. We compared documented features and published prices.

PDF.ai does one job, chatting with PDFs, and prices it simply. The free Hobby plan allows 1 PDF upload and 100 questions a month with a 10MB file limit, enough to try it on one document. Pro costs $10 a month billed yearly and raises the limits to 100 PDFs and 1,000 questions a month, 50MB files and OCR on 10 pages per file for scanned documents. Ultimate at $20 per user a month billed yearly removes upload and question caps, switches to the Advanced AI model and raises OCR to 50 pages per file. A Chrome extension is included on every plan, and developers can use separate Parse, Extract and Chat APIs. The weak spots are the tight free plan and the per-file OCR caps, which matter for long scanned contracts. Pro also uses the Basic model, so harder questions favor Ultimate or a general assistant. We compared documented features and published prices.

SciSpace is built around research papers rather than general documents. Its Chat with PDF page lists citation-backed answers tied to specific sections of the paper, section-wise summaries, simplified explanations of highlighted text, and explanations for maths, equations, tables and figures. Highlighting a passage can also surface related papers, which helps a student building a reading list. The tool supports 75+ languages, and SciSpace says uploads are 256-bit encrypted and not used for data training. Chat with PDF sits inside a larger platform with Literature Review, an AI Writer, a Paraphraser, a Citation Generator and a Chrome extension, so a graduate student can stay in one place from search to draft. The downsides are cost clarity and fit. The pricing page did not show plan prices to our fetch, so we list USD pricing as pending, and the platform uses credits across tools. Workers questioning contracts or invoices will get more from a general assistant. We compared documented features and published prices.

Acrobat AI Assistant puts document chat inside the software most offices already use for PDFs. Adobe's page describes summaries with citations that link to the source in your documents, podcast-style audio overviews of several files, and visual reports and presentations built from your content. PDF Spaces let you gather files, add a custom AI Assistant and share the space so others can ask questions. AI Assistant can also edit, sign, redact and compress documents on request, which no chat-only tool on this list does. Existing Acrobat Reader, Standard or Pro users can sign in and use it, and Acrobat Studio bundles it with Acrobat Pro, PDF Spaces and Adobe Express Premium. Adobe says your content is never used to train its AI models. The downside is cost: there is no permanent free plan, and Adobe's pricing page did not show USD prices from our location, so the price is pending. We compared documented features and published prices.

AskYourPDF suits people who read a lot of long files. The free plan allows 1 document a day of up to 100 pages and 15MB, with 50 questions a day on GPT-5 Mini. Premium at $11.99 a month billed yearly jumps to 2,500 pages per document, 31MB uploads, 50 documents and 1,200 questions a day, and adds a model picker with GPT-5, GPT-5.2 and Gemini 2.5 Flash. Paid plans also include a Knowledge Base for chatting with multiple documents at once, OCR support and a Chrome extension. Pro at $14.99 a month billed yearly raises the ceiling to 6,000 pages per document and 150 documents a day. Beyond PDFs, the conversation tool takes PPT, PPTX, TXT, EPUB and RTF files. The drawbacks: Claude and Gemini Pro models cost extra credits, and the plans bundle a website chatbot that students do not need. We compared documented features and published prices.

ChatPDF is one of the simplest ways to question a document: you drop a PDF on the home page and start asking. Its site says the service summarizes and answers questions for free, and built-in citations anchor responses to PDF references so you can check the page. Folders let you chat with multiple PDFs in one conversation, and ChatPDF accepts PDFs in any language and can reply in any language. It pitches itself at researchers, at students studying for exams and homework, and at professionals reading contracts, financial reports and manuals. Around the chat sit Flashcards, Slides, an AI Writer and an AI Detector, plus chat for YouTube videos and websites. The weak point for buyers is transparency. ChatPDF has a paid Plus plan, but we found no public pricing page and no published usage limits, so we list the price as pending. We compared documented features and published prices.

Sharly AI is aimed at research and analysis work across many documents rather than a single PDF. The free plan includes 50 messages a month with a 10k context length and uploads in PDF, DOCX, PPTX and Notion formats. Pro costs $12.50 a month billed yearly and brings unlimited uploads, 1,000 messages a month, a 50k context length, reasoning capabilities and a pledge of no training data for LLMs. Team at $24 per seat a month billed yearly supports up to 100 seats, lifts message limits, raises context to 124k and adds team annotations, knowledge retention, semantic extraction and citation history. A source-restrict mode keeps answers to your documents only, which helps when you need to show where a claim came from. The free tier is thin for students, and the smaller context window on Pro means very long files may need splitting. Sharly also publishes fewer per-file limits than rivals. We compared documented features and published prices.