AI search engine for scientific research
4.3 Bottom line: Epsilon is a strong research tool, best known for evidence search with inline citations. It has a free plan.
Epsilon scans more than 200 million papers to answer research questions, returning summarized passages with inline references to the underlying sources. You can upload your own papers, build libraries, and synthesize findings across the works you trust. It fits researchers who want cited, evidence-based answers.
| Tool | Rating | Free | From | Best known for |
|---|---|---|---|---|
| Epsilon (this tool) | 4.3 | Yes | $9/mo | Evidence search with inline citations |
 ResearchRabbit | 4.6 | Yes | Free | Citation network visualization |
 Semantic Scholar | 4.6 | Yes | Free | 200M+ paper index |
 NotebookLM | 4.5 | Yes | Free | Answers grounded in your files |
Epsilon is a strong research tool, best known for evidence search with inline citations. It offers a free plan, with paid upgrades from $9/mo.
What makes it different: Epsilon stands out for evidence search with inline citations.
Academic writing and language assistant
Free AI search across academic papers
Summarize papers into structured flashcards
Read and understand research papers