Useful for developers and researchers checking which models build real apps best; pricing isn't published.
Kenning's take
What it does
Code Arena, from Arena (formerly LMArena), has AI models act as coding agents that build web apps and sites in isolated environments while people compare and vote on the output. Votes feed a public leaderboard of coding models. Sessions persist and builds can be shared by link.
- Models build full web projects with file-level tool calls
- Side-by-side model battles
- Public coding leaderboard with confidence intervals
- Persistent, shareable sessions
Who it suits. Developers and researchers comparing how well AI models build real applications.
Key facts
- Category
- Developer tools
- Made by
- Arena (formerly LMArena)
- Released
- 12 November 2025
- How to get it
- in a web browser at arena.ai/code
- Works on
- Web
FAQ
When did Code Arena launch?
Arena's announcement post is dated 12 November 2025.
Who makes Code Arena?
Arena, formerly LMArena and Chatbot Arena, created by researchers from UC Berkeley.
Facts from the maker's own pages and the sources listed. Checked 2026-10-11.
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