Kimi K3.1 Pro hits the API, with full weights promised for November 4

Introducing Kimi K3.1 Pro

Kimi K3.1 Pro went live on the Kimi API today. The weights are not open yet; Moonshot AI says it will release the full model weights on Nov 4, 2026. Its input and output pricing match GPT-6.1 Sol and come in at half of Claude Opus 5.5.

Why it matters: Kimi K3.1 Pro prices input and output at the same rate as GPT-6.1 Sol, half of Claude Opus 5.5.