Moonshot AI Unveils Kimi K3: World's First Open 2.8T Parameter Multimodal Model with Kimi Delta Attention

Moonshot AI has released Kimi K3, crowned as the world's first open 3T-class foundation model, logging over 2.2 million downloads in its first 72 hours.

2.8 Trillion Parameters with Stable LatentMoE

Kimi K3 features a radical sparsity design: while housing 2.8 trillion total parameters, its Stable LatentMoE routing activates just 16 out of 896 specialized experts per token. This delivers a 2.5× improvement in scaling efficiency over the previous Kimi K2 architecture.

Benchmark Dominance in Tool Orchestration

On independent evaluations, Kimi K3 achieved:

• 76.5% on Toolathlon Verified (#1 among open-weights systems).
• 88.3% on Terminal Bench 2.1 for long-horizon terminal tool use.
• 67.5% on DeepSWE (v1.1) software engineering benchmarks.

Kimi K3 integrates native vision encoders, enabling vision-in-the-loop CAD engineering, compiler development, and full-stack autonomous application delivery across 1,000,000 tokens.