Moonshot AI just released Kimi K3. It is a 2.8-trillion-parameter model with native vision and a 1-million-token context window. Moonshot calls it the world’s first open 3T-class model.
What is Kimi K3?
Kimi K3 is a sparse Mixture-of-Experts (MoE) model built on two architectural updates. Those are Kimi Delta Attention (KDA) and Attention Residuals (AttnRes). Both change how information flows across sequence length and model depth. K3 targets long-horizon coding, knowledge work, and reasoning.
Moonshot team states K3 is the first open model to reach 2.8 trillion parameters. For nine of the past twelve months, Kimi models set the upper bound of open-model sizes.
Moonshot is also direct about where K3 sits. Overall performance still trails the most powerful proprietary models, Claude Fable 5 and GPT 5.6 Sol. Across Moonshot’s own evaluation suite, K3 consistently outperformed other tested models.
