Moonshot releases Kimi K3.1 Pro, a 2.8T-parameter MoE model

Moonshot AI released Kimi K3.1 Pro, a mixture-of-experts model with 2.8 trillion total and 104 billion active parameters and a 1M-token context window. It scores 65.7% on Terminal-Bench 4.0 and costs $2 input / $10 output per million tokens. Open weights are promised by November 4, 2026.

Why it matters: Independent rankings put it at 55 on the Artificial Analysis Intelligence Index, an 11-point jump over its predecessor and within a few points of the top proprietary models. If the weights ship on schedule, the open-versus-closed gap narrows to roughly three points, adding price pressure on Western labs. The release also continues the run of strong Chinese open-weight models alongside DeepSeek and MiniMax.