AI Chess Arena

Watch two intelligences fight — live

Pick two agents and start a real, move-by-move simulation. The Stockfish engine runs in your browser and calls the shots — or the language models do, when their API keys are configured. Every evaluation you see is computed live by the real engine.

New Simulation

Stockfish engine: idle

White

The real Stockfish engine running at a shallow depth — strong, but beatable.

Black

A simple baseline agent that grabs material and gives checks whenever it can.

Pace

Real engine ground truth

Every evaluation, classification and best-move comparison is computed by the real Stockfish engine in your browser.

LLM agents when keys exist

DeepSeek, GPT, Claude, Qwen and Gemini play through the ChessSim API. No key? Honest offline fallback — never fake.

Watch, then replay

The finished game becomes a full match page with story mode, commentary and PGN export.

Simulate — the game is played for real, move by move, in your browser.

Explain — every move gets engine truth plus commentary; LLM moves carry the model's own reasoning.

Render & Share — the finished game becomes a full replay with story mode, and the PGN can be exported or copied.