Arena

“Arena, a one-year-old San Francisco startup that runs crowdsourced AI model leaderboards and sells performance analytics to model makers and enterprises, raised a $200 million Series B round at a $3.1 billion valuation, up from $1.7 billion in January.”

“Arena AI data puts the gap between the best closed and open weight models at 29 Elo points as of September 2026.”

“Arena Agent Mode with GitHub — Get real work done, moving from idea to shipping in minutes (86 votes)”