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Explainpaper

AI reading companion that decodes dense academic papers by highlighting and chatting with the PDF.

Freemium· Free; Pro $16/mo with 7-day trialRAGUndisclosed (tiered basic vs. advanced)6.8 / 10

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Best for

Pick Explainpaper if you read a lot of dense academic papers and want an inline highlight-to-explain workflow rather than juggling chatbot tabs.

Skip if

Skip it if you need an API, on-prem deployment, or a general document-Q&A tool that handles contracts, reports, and code as well as papers.

Explainpaper is a research paper reader that wraps an LLM around the PDF reading experience. Upload an academic paper, highlight any confusing passage, and the tool returns a plain-language explanation tuned to a complexity level you choose (beginner through expert). You can also chat with the full paper, ask follow-up questions in context, and pull auto-generated outlines and key points instead of grinding through the abstract and methods sections cold.

It is aimed squarely at grad students, researchers crossing into adjacent fields, and curious non-specialists trying to keep up with arXiv. The free tier covers unlimited highlight explanations and follow-ups, while the $16/month Pro plan unlocks advanced models, full-paper summaries, saved highlights, and translations across 50+ languages. There's a 7-day Pro trial that doesn't ask for a card up front.

It is a closed, hosted SaaS with no public API or self-hosting story, and the site is coy about which underlying models power the free vs. Pro tiers. If you already live in a more general AI workspace (NotebookLM, ChatGPT with PDFs, Claude Projects), Explainpaper's edge is the inline highlight-to-explain UX rather than raw model quality.

Editor's take

Explainpaper nails one job: making arXiv-grade prose readable without leaving the PDF. It's a nice-to-have rather than a must-have now that Claude Projects and NotebookLM can do similar work on any document, but the highlight-first UX is still the most natural way to read a hard paper.

— The AI Tool Bible editorial team

Pros

✅ Highlight-to-explain UX is faster than copy-pasting into a chatbot
✅ Adjustable complexity from beginner to expert
✅ Generous free tier with unlimited highlight explanations
✅ Supports 50+ languages for explanations and summaries

Cons

⚠️ No public API or self-hosting option
⚠️ Underlying models are not disclosed
⚠️ Narrow scope: only works for academic PDFs
⚠️ General-purpose chatbots increasingly replicate the workflow

Use cases

paper-readingresearch-summariesliterature-reviewstudy-aidtranslation

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