Claude APIPaid
Anthropic's AI models via API — excel at long documents, careful reasoning, and following complex instructions.
AI / LLM comparison
Claude API vs Semantic Kernel
Pricing, pros, cons, and ideal use cases — side by side.
Semantic KernelFree
An open-source SDK from Microsoft for integrating LLMs into applications, with a focus on enterprise-grade orchestration in C#, Python, and Java.
At a glance
| Claude API | Semantic Kernel | |
|---|---|---|
| Pricing | PaidPay-as-you-go. Claude Sonnet roughly $3/1M input tokens. Very competitive pricing. | FreeOpen-source (MIT), free. Costs come from the model APIs you call. |
| Category | AI / LLM | AI / LLM |
| Ideal for | Law FirmsAgenciesAccountantsAny SMB wanting AI features | .NET and Java enterprise development teamsOrgs embedding AI into existing applicationsMicrosoft-ecosystem shops |
Pros & cons
Claude API
Pros
- Excellent at long documents
- Strong instruction following
- Great for legal/compliance
- Competitive pricing
Cons
- Requires technical setup
- Smaller ecosystem than OpenAI
- Newer platform
Semantic Kernel
Pros
- First-class C#, Python, and Java support
- Designed to fit into existing enterprise apps
- Backed and maintained by Microsoft
- Clean plugin and function abstractions
Cons
- Smaller ecosystem than Python-first frameworks
- Roadmap is converging with Microsoft Agent Framework
- Less suited to rapid Python prototyping
Which should you choose?
Semantic Kernel is the lighter-weight option (Free), while Claude API sits higher on the pricing ladder (Paid). Claude API is built around law firms; Semantic Kernel leans more toward .net and java enterprise development teams. Shortlist the one whose strengths line up with your biggest constraint.