R Discovery vs Semantic Scholar
Price, platforms and features side by side. The table says where each price was read and when.
R Discovery
Paper discovery app with an AI assistant, PDF chat and audio
Semantic Scholar
Free AI-powered search engine for scientific literature
Where they differ
- R Discovery starts at $69 per year, or $12 billed monthly (US prices). Semantic Scholar is free.
- Only R Discovery lists iOS and Android apps.
- R Discovery also covers chat assistant.
At a glance
| R Discovery | Semantic Scholar | |
|---|---|---|
| Pricing | Free plan | Free |
| Starts at | $69 per year, or $12 billed monthly (US prices) | Free |
| Free plan | Standard recommendations, 3 AI Assistant uses a day, 3 Chat PDF uses a day with 5 file uploads a month, and limited audio and translation. | Entirely free, with no paid plans. Papers can be read without an account; a free account adds a library, email alerts, Research Feeds and author page claiming. |
| Free trial | None listed | None listed |
| Web | ||
| iOS | ||
| Android | ||
| Browser extension | ||
| Made by | Cactus Communications | Allen Institute for AI (Ai2) |
| Price read from | discovery.researcher.life | semanticscholar.org |
| Checked | Oct 5, 2026 | Oct 5, 2026 |
Who each one suits
R Discovery
- Researchers who want a daily feed of new papers in their field
- Reading on a phone: the iOS and Android apps include audio versions of papers
- Readers who want papers translated into their own language
- Paperpal users who want search and writing tools on one subscription
Semantic Scholar
- Free literature search across all fields of science
- Keeping up with new papers through alerts and recommendation feeds
- Developers who need open scholarly data through an API
Worth knowing
R Discovery
- Free accounts get 3 AI Assistant uses and 3 Chat PDF uses a day, with 5 file uploads a month.
- Literature maps, content feeds, multiple projects and Zotero or Mendeley sync are listed for paid plans only.
- The site bills in local currencies, so prices vary by country. The US prices here are from the pricing page's own price data and agree with the US App Store listing.
- Refunds are limited to 30 days after purchase on annual plans and 7 days on monthly plans.
Semantic Scholar
- There is no smartphone app; the FAQ says the site is designed to be used in mobile browsers.
- TLDR summaries are limited to papers in computer science and the biomedical fields.
- Semantic Reader is in beta and covers mostly arXiv papers, and Ask This Paper works on a limited set of papers.
- Unauthenticated API calls share one pool of 1,000 requests per second; an API key starts at 1 request per second.
Key features
R Discovery
- Ask R Discovery
- An AI assistant that answers research questions with references drawn from more than 300 million papers. Free accounts get 3 uses a day.
- Chat PDF
- Upload a paper, or pick one already on R Discovery, and ask questions about it. The free plan allows 3 uses a day and 5 file uploads a month.
- Literature Review
- Finds relevant papers and synthesizes findings, gaps and themes across them. The feature page says it is available only on a desktop or laptop.
- Personalized feed and alerts
- A feed of papers matched to chosen interests, with alerts for new publications in a field. Personalized recommendations and curated content feeds are part of Prime.
- Audio papers and translation
- Listen to papers read aloud and read them in more than 30 languages. Use is limited on the free plan and unlimited on Prime.
- Library and reference manager sync
- Save papers to reading lists. Prime syncs those lists to Zotero or Mendeley automatically and lets collaborators share them.
Semantic Scholar
- Paper search with TLDR summaries
- Searches papers with filters for venue, author, publication type and date. TLDRs are very short AI summaries, available for nearly 60 million papers in computer science, biology and medicine.
- Highly Influential Citations
- A machine-learning model flags the citations where the cited paper had a significant effect on the citing one, so a long citation list has a starting point.
- Library and Research Feeds
- Save papers into folders, share public folders and bulk export citations. Turning on a Research Feed for a folder brings paper recommendations based on its contents.
- Paper and author alerts
- Email alerts report new citations of a chosen paper, or new papers and citations for an author you follow.
- Semantic Reader
- A beta reading view for most arXiv papers, with in-line citation cards, a table of contents, AI skimming highlights and on-demand definitions of terms.
- Academic Graph API and datasets
- A REST API for papers, authors, citations, venues and recommendations, plus downloadable datasets. Most endpoints work without a key.
Plans
R Discovery
Free$0
Standard recommendations, 3 AI Assistant uses a day, and 3 Chat PDF uses a day with 5 file uploads a month. No credit card required.
Prime$69
per year (shown as $6 a month, billed yearly); $12 billed monthly
Unlimited AI Assistant, Chat PDF and Literature Review, literature maps and Zotero or Mendeley sync. Crossed-out prices: $119 a year and $19 a month.
Paperpal Prime$144
per year (shown as $12 a month, billed yearly); $25 billed monthly
Everything in Prime plus Paperpal writing tools, plagiarism and reference checks, Mind the Graph illustrations and research skill courses.
Semantic Scholar
Free$0
Search, TLDR summaries, Semantic Reader, a paper library, alerts and Research Feeds, plus rate-limited API access.
Ways to pay less
R Discovery
- Annual discount
Yearly billing costs about half of monthly
In the US price data, Prime is $69 a year against $12 a month, and Paperpal Prime is $144 a year against $25 a month. Both work out to about 52% less over a year.
Semantic Scholar
No public discounts listed.
