| Demo | Discord | X | FastChat is an open platform for training, serving, and evaluating large language model based chatbots. FastChat powers Chatbot Arena (https://chat.lmsys.org/), serving over 10 million chat requests for 70+ LLMs. Chatbot Arena has collected over 500K human votes from side-by-side LLM battles to compile an online LLM Elo leaderboard. FastChat's core features include: The trai