Moonshot AI Releases Kimi K3, the Largest Open-Weight AI Model Ever Launched

(WS News) – Chinese AI lab Moonshot AI has released Kimi K3, a 2.8 trillion-parameter open-weight model the company says decodes 6.3 times faster than its predecessor, in what is being described as the largest open-weight AI model released to date.

A New Benchmark for Open-Weight Models

Kimi K3’s scale dwarfs most previously released open models, and Moonshot AI says the model outperforms established closed systems on a range of benchmarks. The release uses a mixture-of-experts architecture paired with a technique the company calls delta attention, along with a one-million-token context window, allowing the model to process very long documents or conversations in a single pass.

Part of an Intensifying Global AI Race

The release lands amid a sharper, more consequential phase of global AI competition. It comes the same week Google reportedly delayed the broader release of its own flagship model after internal testing found shortcomings in coding performance and complex reasoning, and as Apple pursues legal action against OpenAI over trade secrets. Open-weight releases from Chinese labs have increasingly pressured US developers to defend their edge in both capability and cost.

Why It Matters

Because Kimi K3’s weights are open, developers and companies worldwide can download, modify and deploy the model without relying on a single vendor’s infrastructure or pricing. That accessibility could accelerate adoption in markets and use cases underserved by the leading closed-source labs, further intensifying competition across the AI industry.