Chatbot Arena, which spun out of a broader research organization called LMSYS, is the handiwork of doctorate students Wei-Lin Chiang and Anastasios Angelopoulos from Berkeley’s Sky Computing Lab. With north of 1 million monthly users, Chatbot Arena is all about helping LLM developers validate claims around their models’ performance, while anyone can test these models and vote for their preferences. Companies such as OpenAI often share versions of their models with the Chatbot Arena team ahead of the models’ release to help fine-tune things before their formal launch.