How it works

From a prompt to a ranking

1. Ask anything

   Type a real task — writing, coding, reasoning, planning. Battle mode is selected by default.

2. Compare answers

   Two anonymous models respond side by side. You do not see names until you vote.

3. Vote

   Pick A, B, a tie, or both bad. Only anonymous Battle votes update Elo (K=32, start at 1000).

4. Names are revealed

   After you vote, both models are named and you can start a new chat from the rail.

This project is a self-hosted replica of arena.ai (formerly lmarena.com), using free-tier OpenAI-compatible APIs and on-device demo models when keys are missing.