FastChat
FastChat is an open platform for training, serving, and evaluating large language model-based chatbots.
FreeWebAPICLIOpen sourceKoreanLLM-basedMultimodal
Visit websitearena.ai
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FastChat is an open platform for training, serving, and evaluating large language model-based chatbots. Known as the release platform for the Vicuna model, it provides an OpenAI-compatible API server for easy integration. It serves as the underlying technology for the LMSYS Chatbot Arena, offering standardized environments and benchmarking tools like MT-bench for model comparison.
Key features
- OpenAI-compatible API
- Support for various LLMs
- Web-based Chat UI
- Distributed Serving Architecture
- Evaluation Tools (MT-bench)
- vLLM & LightLLM Integration
- Multi-model Comparison
Pricing
Use cases
- Serving Open-source LLMs
- Benchmarking Chatbot Performance
- Building LLM API Servers
- Model Training & Fine-tuning
Who it is for
AI ResearchersLLM DevelopersOpen Source Community
Integrations
vLLMHugging FaceLangChainGradio
Tags
LLMVicuna
How we verified this
Company, pricing, and feature details come from the primary sources below and our latest verification pass. When sources disagree, the official source and the most recent check win.
Last verified 08/30/2026Verified sources: 2
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