Moonshot AI unveils world’s largest open-source AI model as China narrows gap with US rivals
Kimi K3 is designed for long-horizon coding, knowledge work and reasoning tasks, according to a blog post by Moonshot AI

Chinese start-up Moonshot AI has launched the world’s largest open-source artificial intelligence model, claiming to outperform leading US systems from Anthropic and OpenAI in some capabilities, as domestic developers race to challenge American dominance.
Parameters, a machine-learning term, measure the complexity of AI systems during training, with a higher figure generally indicating a stronger model.
K3 was designed for long-horizon coding, knowledge work and reasoning tasks, the company said in a blog post.

K3 outperformed Anthropic’s Claude Fable 5 and OpenAI’s GPT-5.6 Sol – two of the most advanced AI systems from US labs – on a few evaluations, including Program Bench and SWE Marathon, according to self-reported benchmark results by the company.