Kimi K3.1 Pro debuts: beats Claude Opus 5.5 on Terminal-Bench 4.0 at ~1/3 the cost
Yuchenj_UW · x · 2026-10-24
Moonshot released Kimi K3.1 Pro, which researchers call the strongest open-source model yet. A Terminal-Bench 4.0 score-vs-cost chart shows Kimi K3.1 Pro max scoring 66% at roughly $5.5 per task, beating Claude Opus 5.5 (65% at $14.5/task) and undercutting GPT-6 Astra max, Claude Fable 5.1 and Claude Sonnet 5.5 on cost-efficiency; GLM-5.3 and DeepSeek-V4.1-Flash-1017 trail the pack.
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