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LlamaIndex vs LangChain(2026)

LlamaIndex is better for teams that need best-in-class for rag. LangChain is the stronger choice if largest ecosystem. LlamaIndex is open-source (from $0) and LangChain is open-source (from $0).

Full feature breakdown, pricing details, and pros & cons below.

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LlamaIndex logo

LlamaIndex

open-source

LlamaIndex is a data framework for LLM applications specializing in connecting LLMs to external data sources — with best-in-class RAG pipelines, data connectors, and indexing strategies.

Starting at $0

Visit LlamaIndex
LangChain logo

LangChain

open-source

LangChain is the most widely used framework for building LLM applications with chains, agents, memory, and retrieval-augmented generation (RAG) — available in Python and JavaScript.

Starting at $0

Visit LangChain

How Do LlamaIndex and LangChain Compare on Features?

FeatureLlamaIndexLangChain
Pricing modelopen-sourceopen-source
Starting price$0$0
RAG pipelines
100+ data connectors
Multi-modal support
Agents
Query engines
Observability
Python + TypeScript
Chains and agents
RAG support
Memory management
Tool calling
LangSmith (observability)
Vector store integrations
Python + JS

LlamaIndex Pros and Cons vs LangChain

L

LlamaIndex

+Best-in-class for RAG
+Rich data connectors
+Strong enterprise adoption
+Active development
Steeper learning curve than LangChain
More complex for simple use cases
Smaller community
L

LangChain

+Largest ecosystem
+Best documentation
+Rapid prototyping
+Massive community
Abstraction can obscure logic
Frequent breaking changes
Over-engineered for simple tasks

Should You Use LlamaIndex or LangChain?

Choose LlamaIndex if…

  • Best-in-class for RAG
  • Rich data connectors
  • Strong enterprise adoption

Choose LangChain if…

  • Largest ecosystem
  • Best documentation
  • Rapid prototyping

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