LMArena
Crowdsourced model leaderboards from the Chatbot Arena team
LMArena, spun out of UC Berkeley's Chatbot Arena project, runs crowdsourced head-to-head AI model evaluations and leaderboards used across the industry. Evals-focused rather than RL environments, but a core evaluation vendor to labs.
Chatbot Arena leaderboard is a de facto industry standard
| Website | lmarena.ai |
|---|---|
| Domains | Multi-Domain, Machine Learning |
| Location | San Francisco, Berkeley |
| Team size | 26-50 |
| Founded | 2024 |
| Funding | $100M seed (a16z, UC Investments, 2025); $150M at $1.7B valuation (Jan 2026) |
| Founders | Anastasios Angelopoulos @ml_angelopoulos, Wei-Lin Chiang @infwinston, Ion Stoica |
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