ChatPDF vs PDF.ai (2026): which should you pick?
As of Nov 13, 2026, we pick ChatPDF: it is second in our ranking of AI research tools, and it grades higher too, 2.8 against 2.4.
Checked Oct 5, 2026 and Nov 12, 2026 · graded Oct 10, 2026 and Nov 12, 2026 by ToolGPA
ChatPDF grades higher on value for money and platforms. They get the same grade on the free plan, features and ease of use.
Price, platforms and features side by side. The table says where each price was read and when.
ChatPDF
Ask questions about PDFs and get answers with citations
Which one is for you
Pick ChatPDF if
- Fits if you want quick answers from a paper or a textbook chapter, with no sign-up
- Works for students turning course notes into flashcards for Anki or Quizlet
Look elsewhere if
- Tight if you're staying free, at 2 documents and 20 messages a day, files of 120 pages and folders of 5
- Skip it if you want a full literature search, as its paper summaries are built from abstracts only
- Watch out: chatting with a full paper works only for open-access papers
- Not for you if you want the price in writing first, since the website sets Plus prices per visitor
- Pricey if you pay monthly, at $14.99 on the US App Store against $89.99 for the year
Pick PDF.ai if
- Fits if you ask questions of one PDF at a time
- Works for developers who want a PDF parsing API
Look elsewhere if
- Tight if you stay free: 1 PDF and OCR on 2 pages per file
- Watch out: the Ultimate plan's API is non-commercial only, and commercial use needs the credit add-on
- Watch out: the chatbot widget is a separate paid plan
- Watch out: monthly-billing prices weren't readable, and the pricing page would not load for us
How we grade them
| 2.8GPAChatPDFGood | 2.4GPAPDF.aiFair | |
|---|---|---|
| Value for money | BPlus is $89.99 a year on the US App Store, about $7.50 a month, the low end of this category, and it lifts the caps on questions, documents and file size altogether. Pay monthly and it's $14.99. The wrinkle: the website sets Plus prices per visitor, so web checkout may not match. | CPro is $10 a month billed yearly, the research middle. Ultimate is $20 per user, which is where the dearest tenth begins. |
| Free plan and trial | CYou can use it without making an account at all. The caps are the ordinary sort, though: 2 documents and 20 messages a day, files of 120 pages or 10 MB, folders of 5 files. One evening of reading and you're done. The better model is kept for Plus. | CThe Hobby plan is $0 for 1 PDF and 100 questions a month. That's one document at a time, so a normal reader outgrows it quickly. |
| Features | CChat beside the page with clickable citations, folders to ask across files, YouTube and website links, flashcards, slides, a writer. The gaps are the listing's own, and they sit in the research half: paper summaries are built from abstracts, and full-paper chat only works on open-access papers. | CChat with a PDF, OCR, chat with all PDFs, capture and ask, an API and a chatbot widget. The listing shows only 1 PDF on Hobby and OCR capped at 2 pages per file, but the core chat job is covered. |
| Ease of use | BNo store rating on record, so the B rests on the listing: open the site, drop in a PDF, start asking, no account needed. Folders and saved history are the only parts that want you signed in. | BNo store rating on record. Upload a PDF and ask: nothing to set up. |
| Platforms and integrations | AWeb, Mac, Windows, iPhone and Android, plus a developer API. Flashcards export to Anki, Quizlet and Brainscape, slides to PowerPoint, writing to Word or Markdown. | BWeb and a browser extension, with an API. |
| Best for | quick answers from a PDF, no sign-up | asking questions of PDFs |
The GPA is the average of the five grades: an A is 4 points, an F is none. The full reasons are on each tool's page: ChatPDF and PDF.ai. How we grade
Price against what you get
ChatPDF starts at $7.50 a month when paid by the year and scores 3.0 out of 4 on features, ease of use and platforms. PDF.ai starts at $10 a month and scores 2.7.
ChatPDF scores higher and starts $2.50 a month lower. Of the other AI research tools on the chart, none scores higher than ChatPDF for less, and 3 score higher than PDF.ai for less.
Features, ease of use and platforms, averaged
What paid plans start at, a month (each step along is roughly double) →
- The best score at each price
- Has a free plan
- No free plan
Where they differ
- ChatPDF also covers AI search and citations.
- PDF.ai also covers documents.
At a glance
| ChatPDF | PDF.ai | |
|---|---|---|
| Pricing | Free plan | Free plan |
| Starts at | $89.99 per year or $14.99 per month (US App Store in-app purchase) | $10 per month, billed yearly |
| Free plan | 2 documents a day, usable without an account. A free account adds saved history and multi-file folders. Free files are capped at 120 pages or 10 MB. | Hobby: 1 PDF, 100 questions a month, 10 MB files and OCR on 2 pages per file. |
| Free trial | None listed | None listed |
| Web | ||
| macOS | ||
| Windows | ||
| iOS | ||
| Android | ||
| Browser extension | ||
| Made by | ChatPDF GmbH | PDF.ai |
| Price read from | apps.apple.com | pdf.ai |
| Checked | Oct 5, 2026 | Nov 12, 2026 |
Worth knowing
ChatPDF
- The website shows Plus prices only in an upgrade dialog and sets them per visitor; the prices here are US App Store in-app purchases, and web checkout may differ.
- The free plan covers 2 documents a day, and the site's limits cap free use at 20 messages a day and files of 120 pages or 10 MB.
- AI Research summaries are built from abstracts, and chatting with a full paper works only for open-access papers.
- The best model is reserved for Plus; ChatPDF says it routes queries between GPT-4o and GPT-4o-mini.
PDF.ai
- Monthly-billing prices were not readable; the prices shown are those billed yearly.
- The Ultimate plan's API is for non-commercial use only; commercial use needs the credit add-on.
- The chatbot widget is a separate paid plan.
Key features
ChatPDF
- Chat with documents
- Ask questions about a PDF, Word, PowerPoint, Markdown or text file with the chat and the document side by side. Clickable citations scroll to the passage an answer came from.
- Multi-file folders
- Put files in a folder to ask questions across all of them in one conversation. Folders and saved chat history need a free account.
- AI Research
- Ask a question to find academic papers and get a summary with citations, built from the papers' abstracts. Filters narrow results to recent or influential work.
- YouTube and website chat
- Paste a YouTube or website link to ask questions about it. Video answers include clickable timestamps and an interactive transcript.
- Flashcards, slides and writing
- Makes flashcards that export to Anki, Quizlet, Brainscape or CSV, and slides that export to PowerPoint. The AI Writer drafts text with citations and exports to Word or Markdown.
- Developer API
- A backend API adds PDFs by URL or file upload and answers questions about them, with optional page references. API files are limited to 2,000 pages or 32 MB.
PDF.ai
- Chat with PDFs
- Ask questions about an uploaded PDF; limits on uploads and questions depend on the plan.
- OCR
- AI-powered OCR for scanned files, from 2 pages per file on Hobby up to 100 on Enterprise.
- Chat with all PDFs
- Ultimate and above can question the whole library at once.
- Capture and ask
- Ultimate and above can capture a screenshot and ask about it.
- API
- Parsing, extraction and splitting API; commercial use is an add-on from $50 a month for 1,000 credits.
- Chatbot widget
- Ultimate users can add a paid widget so visitors chat with PDFs hosted on a site.
Plans
ChatPDF
Free$0
2 documents and 20 messages a day, with files of up to 120 pages or 10 MB and folders of up to 5 files.
Plus$14.99
per month on the US App Store; $89.99 for the yearly plan
Unlimited questions and documents, files of up to 2,000 pages or 150 MB, 50 PDFs per folder and the higher-quality model.
PDF.ai
Hobby$0
1 PDF, 100 questions a month, 10 MB max file, OCR on 2 pages per file.
Pro$10
per month, billed yearly
100 PDFs, 1,000 questions a month, 50 MB files, OCR on 10 pages per file.
Ultimate$20
per user / month, billed yearly
Unlimited PDFs and questions, advanced AI model, chat with all PDFs, team members.
Enterprise$30
per user / month, billed yearly
Unlimited use, 100 MB files, OCR on 100 pages per file, white-labeled PDF embed.
Ways to pay less
ChatPDF
- Annual discount
About 50% off with the yearly plan
On the US App Store the yearly Plus plan is $89.99 against $14.99 a month. That works out to about $7.50 a month, half the monthly rate.
PDF.ai
- Annual discount
Save 25% with yearly billing
The pricing page shows a Payment frequency toggle with Annually labeled as saving 25%.
Common questions
Which is cheaper, ChatPDF or PDF.ai?
As of Nov 12, 2026, ChatPDF is cheaper to start with: $7.50 a month when paid by the year, against $10 a month for PDF.ai. ChatPDF starts at $89.99 per year or $14.99 per month (US App Store in-app purchase), and PDF.ai starts at $10 per month, billed yearly.
Which has a free plan, ChatPDF or PDF.ai?
As of Nov 12, 2026, both ChatPDF and PDF.ai have a free plan.
Which platforms do ChatPDF and PDF.ai run on?
As of Nov 12, 2026, only ChatPDF lists macOS, Windows, iOS and Android apps and only PDF.ai lists a browser extension. Both list a web app. A platform missing from a listing is one its maker's pages did not mention.
More comparisons
How this page was made
- The verdict at the top follows a fixed rule. When both tools are in the same category and either is in our top three for it, the verdict follows that ranking: the higher-placed tool is our pick. The top three weigh who each tool suits as well as its grades, so a pick can go against the GPA. Otherwise the page does not pick one and says which grades higher: the higher GPA first; on a tie, the one with a free plan, then the one that starts cheaper in dollars a month, counted the same way for both; if they are still level, what the choice depends on.
- The grades are our own, from each tool’s review or report card. The GPA is their average.
- Prices, plans and platforms come from each tool’s listing. The table above says where each price was read and when.
- The differences and the answers to the questions are worked out from those listings.