Meet Kimi K3.1 Pro, our most capable 3T-class model.

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Reported by 3 sources

The story so far

Kimi launched K3.1 Pro and K3.1 Pro Highspeed across Kimi.ai, Kimi Work, Kimi Code and the Kimi API, with model weights promised by November 4, 2026. Baoyu also reported same-day access to K3.1 Pro through the Kimi app. Kimi describes K3.1 Pro as a multimodal mixture-of-experts model with a 1 million-token context window, 2.8 trillion total parameters and 104 billion active parameters. The company says Highspeed is 2–3 times faster and claims K3.1 Pro reduces hallucinations in finance work by 65%. Nathan Lambert identified K3.1 Pro as the previously tested K3.1 and said its benchmark scores appeared strongest among current open-weight models, conditional on the promised weights release. Before launch, Leifeng.com reported strong Three.js and interactive 3D results in user tests, alongside an awkward-looking giraffe animation; one comparison put its cost at about one-fourteenth that of GPT-6 Astra. Lambert separately said K3.1 costs less per token than K3, but higher token use on some benchmarks could leave the cost per answer similar.