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Arena

Arena (formerly LMArena) runs a crowdsourced leaderboard where millions of users blind-vote on outputs from competing AI models each month. Grown out of UC Berkeley research as LMSYS Chatbot Arena, it rebranded to Arena in January 2026 after raising a $150 million Series A at a $1.7 billion valuation.

arena.ai ↗ Hear the team
Business model
B2B SaaS (AI model evaluation)
Founders
Wei-Lin Chiang, Anastasios N. Angelopoulos, Ion Stoica

Sources: arena.ai, techcrunch.com

1person interviewed
1episode across 1 show
1mention in other conversations

The team on Day One

Peter Gostev Head of AI Capabilities, Arena (LMArena) “A model can pass every test you write and still produce something that looks completely awful.” 1 episode →

Hear from the team

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3 July 2026 · In The Blink Of AI How AI Models Are Really Judged, with Peter Gostev (Arena / LMArena) Peter Gostev

Milestones

  1. 2023 Launched as Chatbot Arena, a UC Berkeley research side project dailycal.org
  2. May 2025 Raised $100M seed at $600M valuation, led by a16z and UC Investments bloomberg.com
  3. Jan 2026 Raised $150M Series A at $1.7B valuation techcrunch.com

What others say about Arena

Moments from other conversations on the network where Arena comes up.

My understanding is that as an industry, we typically look at— things change names a couple of times— LM Arena, I think it's called nowadays, or Chatbot Arena.”
Oscar WahltinezSenior Developer Programs Engineer, Google In The Blink Of AI · Oscar Wahltinez (Google) on the Truth Ab… · 21:41 ▶

In the news

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Spot something wrong? Suggest a correction Updated 25 September 2026

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