head to head · open source
langchain vs R2R
langchain has 146,562 GitHub stars, 24,508 forks, 492 open issues and last shipped today. R2R has 7,998 stars, 647 forks, 126 open issues and last shipped 11 months ago. langchain leads on adoption by 1,732% (146,562 vs 7,998 stars). langchain is written in Python under MIT; R2R is written in Python under MIT. langchain has attracted 17% as many forks as stars, R2R 8%. langchain was the more recently maintained of the two, and both are self-hostable with no licence fee.
Two open source projects, one decision. Both are free and self-hostable — the differences are community size, license terms, language stack and release pace.
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Side by side
| langchain | R2R | |
|---|---|---|
| GitHub stars | ★ 147K | ★ 8.0K |
| License | MIT | MIT |
| Written in | Python | Python |
| Last push | 2026-09-18 | 2025-11-07 |
| Forks | ⑂ 25K | ⑂ 647 |
| Self-hosting | Yes | Yes |
| Data ownership | Your server | Your server |
pick langchain if
- You weight community size — 147K stars and counting
- You want the MIT license terms
- Your stack matches Python
- You value the larger contributor base for long-term maintenance
pick R2R if
- You want the R2R feature set and don't need the biggest community
- You prefer the MIT license terms
- Your stack matches Python
- You evaluated both and R2R fits your workflow better
About langchain
LangChain is an open source framework for building agents and LLM powered applications, written in Python and released under the MIT license. It lives in the AI and machine learning ecosystem, specifically among AI development platforms, and it works by chaining together interoperable components and third party integrations so that AI application development becomes simpler. The project describes itself as the agent engineering platform, and its abstractions are designed to keep applications working as the underlying technology evolves.
read the full langchain overview →
About R2R
R2R is an MIT licensed, Python based retrieval system from SciPhi AI that gives developers a RESTful API for agentic Retrieval Augmented Generation over their own documents, with official Python and JavaScript clients.
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Frequently asked questions
Is langchain or R2R more popular?
langchain has 146,562 GitHub stars and R2R has 7,998. langchain has the larger community by that measure.
Are langchain and R2R free?
Both are open source. langchain is licensed under MIT and R2R under MIT. Neither carries a licence fee.
What is the difference between langchain and R2R?
langchain is written in Python and R2R in Python. The practical differences are community size, licence terms, language stack and release cadence — all compared in the table above.
Which should I choose, langchain or R2R?
Choose langchain if you want the larger community (146,562 stars) or its MIT licence terms. Choose R2R if its feature set, stack or MIT licence fits better. Both are self-hostable.