Codex Build Arena

See what more Codex thinking actually buys you

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Codex Build Arena is an open, visual benchmark of complete apps produced from the exact same one-shot prompt and starter repository. Compare GPT-5.6 Luna, Terra, and Sol across effort levels through live builds, side-by-side previews, engineering reviews, token usage, credits, duration, and source size. No cherry-picking, follow-up prompts, or hidden repairs. Use the results and decide which model and effort earned the cost.

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