Open-Source AI · LLM / RAG framework

LlamaIndex vs Semantic Kernel

LlamaIndex vs Semantic Kernel compared for 2026 — features, license, ease of use, performance and which one to choose. The data framework for RAG vs Microsoft's enterprise agent framework.

Updated regularly · curated by OpenSourceAI.tech

Choose LlamaIndex for developers building data-heavy RAG apps. Choose Semantic Kernel for enterprise teams on the Microsoft stack.

LlamaIndex vs Semantic Kernel at a glance

SpecLlamaIndexSemantic Kernel
CategoryLLM / RAG frameworkLLM / RAG framework
TypeData / RAG frameworkLLM orchestration SDK
LicenseMITMIT
Runs locallyCloud-optionalPartial
Primary languagePythonC#/Python
Ease of useIntermediateIntermediate
Best fordevelopers building data-heavy RAG appsenterprise teams on the Microsoft stack
GitHub stars50.9k28.3k

Feature comparison

FeatureLlamaIndexSemantic Kernel
Python✓✓
JavaScript / TS✓✗
Agents✓✓
RAG✓✓
Streaming✓✓
Many integrations✓✓

How LlamaIndex and Semantic Kernel score

🤝 Too close to call — LlamaIndex and Semantic Kernel land within a hair (4.3 vs 4.1 / 5). Pick on fit, not on score.
CriterionLlamaIndexSemantic Kernel
Popularity4.53.5
Maintenance5.05.0
Ease of use3.53.5
Privacy3.53.5
License freedom5.05.0

Scores are computed automatically from public signals — GitHub stars (popularity), recent commit activity (maintenance), license type (freedom), local-first design (privacy) and onboarding complexity (ease of use). Indicative, not a verdict.

What each one is

LlamaIndex

Data / RAG framework · MIT

LlamaIndex is a data framework focused on connecting LLMs to your data, with best-in-class ingestion, indexing and retrieval for RAG applications.

  • Best-in-class ingestion and indexing for RAG
  • Many data connectors and retrievers
  • Focused, RAG-first design
See the LlamaIndex page →

Semantic Kernel

LLM orchestration SDK · MIT

Semantic Kernel is Microsoft's open SDK for building AI agents and orchestrating models in .NET, Python and Java, with plugins, planners and enterprise-grade patterns.

  • First-class .NET, Python and Java support
  • Enterprise patterns: planners, plugins, filters
  • Backed and used by Microsoft at scale
See the Semantic Kernel page →

Key differences

LlamaIndex is data / RAG framework, while Semantic Kernel is lLM orchestration SDK. They also differ in how they run (Cloud-optional vs Partial). In short, LlamaIndex fits developers building data-heavy RAG apps, and Semantic Kernel fits enterprise teams on the Microsoft stack.

Which should you choose?

Choose LlamaIndex for developers building data-heavy RAG apps. Choose Semantic Kernel for enterprise teams on the Microsoft stack.

There is rarely one winner — many setups use both. The right pick depends on your hardware, your team's skills, and whether you value simplicity or control.

Frequently asked questions

Is LlamaIndex or Semantic Kernel easier to use?

Both sit at a similar level (Intermediate). Your choice should come down to fit rather than difficulty.

Are LlamaIndex and Semantic Kernel free?

LlamaIndex is free and open source (MIT), and Semantic Kernel is free and open source (MIT). Neither charges for the core software.

Can I run LlamaIndex and Semantic Kernel locally?

LlamaIndex: cloud-optional · Semantic Kernel: partial. Both can be used without sending your data to a third-party cloud where their setup allows.

LlamaIndex vs Semantic Kernel — which should I pick in 2026?

Choose LlamaIndex for developers building data-heavy RAG apps. Choose Semantic Kernel for enterprise teams on the Microsoft stack.

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