Overview

Explainpaper lets you highlight confusing passages and receive explanations in adjustable complexity and more than 50 languages. Because responses use the full paper context, it is better suited to terminology and arguments that depend on surrounding text than a generic chatbot working from an isolated excerpt.

Paper chat answers questions about a paper, supports follow-up questions and can summarize findings. Citations point to specific sections, so a reader can move from an answer back to the relevant passage instead of treating the response as an unsupported conclusion. The product also creates smart outlines, extracts key points and maps relationships between concepts, giving a paper a usable structure before close reading.

Key features

Contextual explanations

Highlight explanations are unlimited on Free, and the adjustable complexity makes the same passage useful to a newcomer or a more advanced reader. More than 50 language options broaden its use for international research teams and readers working outside their first language.

Questions and citations

Paper chat combines direct answers with follow-up questions and finding summaries. Section-level citations are a meaningful safeguard for academic reading: they make it quicker to verify where an answer came from.

Research workflow

Zotero library import is included on Free, while Pro adds saved highlights and explanations, whole-paper summaries, paper questions, advanced models, and Math Explain for formulas and figures. Those upgrades matter most during repeated reading or technical work; casual readers can stay with passage explanations and basic models.

Pricing

Plan	Price	What it includes
Free	Free for everyone, forever	Unlimited highlight explanations, follow-up questions, Zotero library import and basic AI models
Pro	16.00 USD per month, billed $16/month	Math Explain for formulas and figures, advanced AI models, whole-paper summaries, saved highlights and explanations, and paper questions
Teams	Custom pricing	Everything in Pro, plus team management, priority support and volume discounts

The indefinite Free plan is unusually practical for readers who mainly need explanations and follow-up questions. It gives up Pro’s advanced models, formula and figure help, full-paper summaries, saved work and dedicated paper-question feature, so intensive researchers will outgrow it. Pro has a 7-day free trial and requires a card; subscriptions renew monthly or annually according to the selected plan. Stripe processes payments, and card details are not stored on Explainpaper’s servers. Billing questions go to founders@explainpaper.com.

Platforms

Explainpaper is available on the web. That makes it straightforward for desktop paper reading, but the product is not presented as a native mobile app.

Who it's for

Students and researchers who regularly encounter dense passages are the clearest fit, especially those already organizing papers in Zotero. Multilingual readers benefit from the language range, while technical researchers gain the most from Pro’s Math Explain and advanced models. Teams that need centralized administration, priority support or volume pricing should ask about Teams. It is less compelling for someone who only needs occasional document chat and does not value paper-specific context or citations.

Pros and cons

Pros

Unlimited core reading help: Free covers highlight explanations and follow-up questions indefinitely.
Paper-grounded answers: Full-paper context and section citations make responses easier to check.
Useful academic workflow: Zotero import, outlines, key-point extraction and concept relationships support structured reading.
Strong technical upgrade: Pro adds Math Explain, advanced models, summaries and saved explanations.

Cons

Web only: Readers seeking a dedicated mobile app have no native platform option presented.
Pro is required for several advanced tasks: Formula and figure explanations, whole-paper summaries and saved work are outside Free.
Trial has a payment hurdle: The 7-day Pro trial requires a card.
Team cost is uncertain: Teams uses custom pricing, so budgeting requires a direct inquiry.

Alternatives

AskYourPDF is a better fit if you need broad device coverage, an API or extension, and a Premium plan with 2,500 pages per document, 31MB uploads, 50 documents per day and 1,200 questions per day for $11.99 per year billed yearly. Choose Audeus instead when listening is central: it offers standard free voices, cross-device playback and document text-to-speech, with limited uploads and Pro-voice access.

Paperpal suits researchers prioritizing writing and editing through extension and web access. ResearchPal AI Paraphraser is the better choice for bounded literature-review and paraphrasing work, with a Free plan limited to 15 monthly credits, five papers, one project, one literature review and one 500-word AI plagiarism check. Humata offers API access and a Free allowance of 60 pages monthly for one user, while its Team plan provides 5,000 free pages monthly for 10 users at $49 per user per month.

ChatPDF is preferable for broad operating-system coverage and simple document chat; its Free plan allows two documents per day. Anara fits collaborative, connected workflows, with Google Drive, Notion and OneDrive connectors and up to 300MB or 10,000 pages per upload on Pro. DeinPDF is for occasional, usage-based work across Android, iOS and web, with no monthly base fee and top-ups from €10. For category browsing, see AI PDF Assistants, AI PDF Tools and AI Study Tools.

Verdict

Choose Explainpaper if you read research papers often and want explanations, questions and citations tied to the paper itself, with a genuinely usable Free plan. Look elsewhere if you need native mobile software, audio-first reading, or a clearly priced team and high-volume document service.

	Explainpaper	PDFpal
Free plan	Yes
Free trial	Yes	No
Paid from	$16/mo
Platforms	Web	api, self-hosted, Web
Free plan	Yes
Source citations	Yes	Yes
Access platforms	web	web
Multiple PDFs per chat		Yes

Explainpaper vs PDFpal

Explainpaper

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