LangChain vs LlamaIndex
RAG framework showdown — which is better for building AI-powered search?
12 min read•Tools: LangChain, LlamaIndex•Updated Feb 2026
L
LangChainL
LlamaIndexQuick Recommendation
LangChain
Best for AgentsChoose if you need:
- ✓You are building complex multi-step agent workflows
- ✓You need extensive tool calling and function integration
- ✓Your app requires chains, routers, and orchestration logic
- ✓You want the largest ecosystem of integrations and connectors
LlamaIndex
Best for RAGChoose if you need:
- ✓RAG over your own documents is the primary use case
- ✓You need advanced indexing strategies (tree, keyword, knowledge graph)
- ✓You want simpler, more focused APIs for data ingestion and retrieval
- ✓Your project centers on search and Q&A over structured/unstructured data
Side-by-Side Comparison
| Feature | LangChain | LlamaIndex |
|---|---|---|
| Primary Focus | Agent orchestration & chaining | Data indexing & retrieval (RAG) |
| RAG Quality | Good (basic retrievers) | Excellent (advanced index types) |
| Agent Support | Excellent (LangGraph for stateful agents) | Good (Workflows API) |
| Data Connectors | 150+ document loaders | LlamaHub (160+ connectors) |
| Learning Curve | Steep (large API surface) | Moderate (focused API) |
| TypeScript SDK | LangChain.js (mature) | LlamaIndex.TS (stable) |
| Observability | LangSmith (built-in tracing) | LlamaTrace, OpenTelemetry |
| Pricing | Open source (LangSmith paid) | Open source (LlamaCloud paid) |
Our Verdict
If your primary goal is building a RAG pipeline that answers questions over your documents, LlamaIndex is the more focused and often simpler choice. If you need agent workflows that combine RAG with tool use, API calls, and multi-step reasoning, LangChain offers a broader orchestration layer. Many production systems use both together, with LlamaIndex handling retrieval and LangChain managing the outer agent loop.
Frequently Asked Questions
Need help choosing between LangChain and LlamaIndex?
Our engineers have production experience with both tools. We can help you make the right choice based on your specific requirements, timeline, and budget.