Quick answer
Connected Papers builds a similarity graph around one seed paper, showing prior and derivative work; five free graphs a month, Academic plan from $6. ResearchRabbit is free, maps citation and author networks across collections you build, recommends new papers as the collection grows, and syncs with Zotero. Use Connected Papers to orient on a topic fast; use ResearchRabbit to run an ongoing literature review.
Keyword search finds papers that use your words. It misses the paper that uses different words for the same idea, which is often the one you needed. Graph tools find it by following citations and similarity instead of vocabulary.
Connected Papers: one paper in, a map out
Paste a paper and Connected Papers draws a graph of the works most similar to it, based on overlapping citations rather than direct links, with lists of the foundational prior works and the derivative works that built on it. It takes seconds and needs no account for the free graphs. It is not a collection manager; when you have found the papers, you take them elsewhere.
ResearchRabbit: a collection that grows
ResearchRabbit is built around collections. Add papers, and it maps their citations and authors, suggests related work, and emails you when new relevant papers appear. Two-way Zotero sync means the collection is your library. It is free, which for a tool this useful remains surprising, and its visualisations get crowded once collections are large.
Using both
- Start a new topic with a Connected Papers graph from the best paper you know
- Move the papers worth reading into a ResearchRabbit collection and let it recommend more
- Add Semantic Scholar alerts for the field if you want a third net
- Neither summarises or extracts; pair with Elicit, Consensus, or scite for that
Bottom line
Connected Papers for fast orientation. ResearchRabbit for an ongoing review with alerts and Zotero. Both are cheap or free, so the answer for most researchers is both.
