Free AI search across academic papers
Bottom line: Semantic Scholar is a top-tier research tool, best known for 200M+ paper index. It has a free plan.
Semantic Scholar is a free academic search engine from the Allen Institute for AI that indexes over 200 million papers across every field. It highlights influential citations, extracts key figures, and offers TLDR summaries so you can judge relevance quickly. Researchers and developers also use its open API to build their own tools.
| Tool | Rating | Free | From | Best known for |
|---|---|---|---|---|
 Semantic Scholar (this tool) | 4.6 | Yes | Free | 200M+ paper index |
 ResearchRabbit | 4.6 | Yes | Free | Citation network visualization |
 NotebookLM | 4.5 | Yes | Free | Answers grounded in your files |
 Connected Papers | 4.5 | Yes | $5/mo | Similarity-based paper graphs |
Semantic Scholar is an excellent research tool, best known for 200M+ paper index. It offers a free plan.
What makes it different: Semantic Scholar stands out for 200M+ paper index.
Ask questions across your documents
Visual citation mapping for literature reviews
AI search engine for scientific research
Visual graphs of related research papers