LangChain

Compose chains, tools and agents
LLM / RAG frameworkLLM app frameworkMITCloud-optionalPython / JSIntermediate
🛡 Published security advisories
A high count usually means the project is heavily examined. A low count usually means it is little examined — not that it is safe.
No public activity signals for this tool — it has no open repository we can measure.
OSAI Pulse ⓘ ★★★★★★★★★★ /100 signals tracked
🐳 Docker pulls 📦 PyPI downloads / month 📦 npm downloads / month 🚀 Latest release ·
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What is LangChain?

LangChain is a framework for building LLM applications by composing prompts, models, tools, memory and agents, with a vast ecosystem of integrations.

Why people choose LangChain

LangChain at a glance

CategoryLLM / RAG framework
TypeLLM app framework
LicenseMIT
Runs locallyCloud-optional
Built withPython / JS
Skill levelIntermediate
Best fordevelopers building tool-using LLM apps

Open-source alternatives to LangChain

Other open-source llm / rag framework tools worth comparing:

LlamaIndexThe data framework for RAGHaystackProduction pipelines for search and RAGDSPyProgram — not prompt — language modelstxtaiAll-in-one embeddings databaseRAGFlowDeep-document-understanding RAGSemantic KernelMicrosoft's enterprise agent frameworkGraphRAGRAG that builds a knowledge graph firstLiteLLMOne API for 100+ LLM providersInstructorReliable structured outputs from LLMsOutlinesGuarantee valid JSON and grammarsGuidanceInterleave control and generationLLMWareEnterprise RAG with small specialised modelsFlashRankUltra-light reranking for better RAGSentence TransformersThe standard way to make embeddingsRagasMeasure whether your RAG is any goodPromptfooUnit tests for your promptsLangfuseSee what your LLM app actually didPhoenixTrace, evaluate and debug LLM apps

LangChain head-to-head

LangChain vs LlamaIndexLangChain vs HaystackLangChain vs DSPyLangChain vs txtaiLangChain vs RAGFlowLangChain vs Semantic KernelLangChain vs GraphRAGLangChain vs LiteLLMLangChain vs InstructorLangChain vs OutlinesLangChain vs GuidanceLangChain vs LLMWareLangChain vs FlashRankLangChain vs Sentence TransformersLangChain vs RagasLangChain vs PromptfooLangChain vs LangfuseLangChain vs Phoenix

FAQ

Is LangChain free?

LangChain is free and open-source (MIT license), so you can use, self-host and modify it at no cost.

Can I run LangChain locally?

LangChain can be used locally or in the cloud depending on your setup.

What is the best alternative to LangChain?

Popular open-source alternatives include LlamaIndex, Haystack, DSPy. See the comparisons above to choose.

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