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EvalLMArena

LMArena

Crowdsourced LLM leaderboard where humans vote on anonymous model battles.

Category
Eval
Pricing
FREE
Hosting
Cloud
Platforms
Web
Models
Multi-model
Verified
Jun 15, 2026

An open evaluation platform where a user enters a prompt, two anonymous models answer side by side, and the user picks the better response. Those millions of blind pairwise votes are aggregated into Elo-style rankings across text, vision, coding, and other arenas. It works directly with major AI labs and has become the most-cited public reference for comparing frontier model quality.

Capabilities 2

What it actually does — grouped by capability family.

  • Multi-model access (secondary capability)
  • LLM evaluation (primary capability)

Pros & cons

  • Real human preference votes
  • Covers all major frontier models
  • Free and open to use
  • Widely cited industry standard
  • No public API yet
  • Crowd votes can be noisy or gamed
  • A leaderboard, not a dev test harness

Tags

Further reading

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