Explainpaper
Highlight any passage in a research paper and get a plain-language explanation.
About
Explainpaper is a reading assistant for academic papers with one tight job: upload a research PDF, highlight any confusing sentence, and get a context-aware explanation in plain language. You can ask follow-up questions, adjust explanation complexity from beginner to expert, and get explanations in more than 50 languages. Pro features include Math Explain for formulas and figures, whole-paper summaries, saved highlights and explanations, and paper outlines, plus Zotero library import on the free plan.
The free tier is genuinely usable, with unlimited highlight explanations and follow-up questions running on basic models, while Pro at $16 per month (with yearly billing saving 25%) adds the advanced models and full-paper features. An October 2026 educator review confirmed the current feature split and noted it as a solid single-paper reading companion alongside broader tools like NotebookLM.
The limits are worth stating plainly. Explanations of dense math passages can be confidently wrong, reviewers advise cross-checking against the original notation, and the tool's presence does not establish that it improves comprehension. It is a good explainer for jargon and methods sections, not an authority on whether the paper is right.
What it can do
- Highlight-to-explain for any passage in a PDF
- Context-aware explanations adjustable from beginner to expert
- Explanations in 50+ languages
- Math Explain for formulas and figures (Pro)
- Whole-paper summaries and outlines (Pro)
- Saved highlights and explanations (Pro)
- Zotero library import on the free plan
- arXiv URL import
Setup
- Create a free account at explainpaper.com.
- Upload a research PDF or paste an arXiv URL.
- Highlight any confusing passage to get a plain-language explanation.
- Ask follow-up questions and adjust the complexity level.
- Upgrade to Pro at $16/mo for Math Explain, whole-paper summaries, and saved highlights.
Prerequisites
A free account; a research paper in PDF form.
Use cases
Works with
Trust score — 6/10
Scored 6/10 (metrics tier, metrics-v1). Evidence: free plan with unlimited highlight explanations; Pro $16/mo with Math Explain, whole-paper summaries, saved highlights (aitools.fyi, corroborated by educatorstechnology.com Oct 2026 review); arXiv URL import and Zotero integration (github.com ai-megalist). Docs corroboration: feature split consistent across aitools.fyi, educatorstechnology.com, and thataicollection.com. Strengths: generous free tier, transparent per-plan feature split, recently reviewed by an educator outlet. Docked for: (1) third-party sources conflict on legacy plan names and prices ($12/$16/$20), suggesting pricing has shifted; (2) math explanations can be confidently wrong and need cross-checking (educatorstechnology.com, ai-megalist); (3) no major funding or adoption figures publicly documented. License: proprietary SaaS, freemium.
How the trust score is built
Full methodology →- Adoption · stars/downloads, log-scaled vs peers
- 5.0/10
- Maintenance · recency, releases, issue load
- 6.0/10
- Openness · license + docs
- 7.0/10
- Manual review · sanity read + red-flag check
- 6.0/10
- · Free plan with unlimited highlight explanations and follow-up questions; Pro $16/mo with Math Explain, whole-paper summaries, saved highlights (aitools.fyi; educatorstechnology.com Oct 2026 review)
- · arXiv URL import and Zotero library import on free plan (github.com ai-megalist)
- · Third-party sources conflict on legacy plan names/prices ($12/$16/$20), suggesting pricing has shifted over time (thataicollection.com)
Sources
Every fact above was checked against these sources. Where a claim comes from the provider and couldn't be independently verified, the text says so.