📰 Tech Blog | 📄 Full Report
1. Model Introduction
Kimi K3 is an open-weight, native multimodal agentic model and our most capable model to date. It is a 2.8T-parameter model built on Kimi Delta Attention (KDA) and Attention Residuals (AttnRes), with native vision capabilities and a 1-million-token context window. It is the world's first open 3T-class model, designed for frontier intelligence across long-horizon coding, knowledge work, and reasoning.
Key Features
- New Architecture: Kimi K3 is built on Kimi Delta Attention (KDA) and Attention Residuals (AttnRes), and scales up MoE sparsity with a Stable LatentMoE framework that activates 16 out of 896 experts — yielding an approximate 2.5× improvement in overall scaling efficiency over Kimi K2.
- Long-Horizon Coding: Operating with minimal human oversight, Kimi K3 sustains long engineering sessions, navigates massive repositories, and orchestrates terminal tools — from GPU kernel optimization and compiler development to vision-in-the-loop game dev, CAD, and even chip design.
- Agentic Knowledge Work: Kimi K3 advances end-to-end knowledge work, producing deep research with interactive visualizations, widgets and dashboards, and motion design and video editing, powered by its native multimodal architecture.
- Native Multimodality & Long Context: Kimi K3 understands text, images, and video within the same model, and supports a 1-million-token context window.
- Open Frontier Weights: We release the full Kimi K3 model weights under the Kimi K3 License, making frontier intelligence openly available for research, deployment, and further innovation.
2. Model Summary
| Architecture |
Mixture-of-Experts (MoE) |
| Total Parameters |
2.8T |
| Activated Parameters |
104B |
| Number of Layers |
93 |
| Number of Dense Layers |
1 |
| Attention-Layer Composition |
69 KDA + 24 Gated MLA |
| Attention Hidden Dimension |
7168 |
| Number of Attention Heads |
96 |
| Latent MoE Dimension |
3584 |
| MoE Hidden Dimension (per Expert) |
3072 |
| Number of Experts |
896 |
| Selected Experts per Token |
16 |
| Number of Shared Experts |
2 |
| Vocabulary Size |
160K |
| Context Length |
1048576 |
| Attention Mechanism |
KDA & Gated MLA |
| Activation Function |
SiTU-GLU |
| Vision Encoder |
MoonViT-V2 |
| Parameters of Vision Encoder |
401M |
| Quantization |
MXFP4 weights / MXFP8 activations (quantization-aware training) |
| Modality |
Text, Image |
3. Evaluation Results
| Benchmark |
Kimi K3 (max) |
Claude Fable 5 (max, w/ fallback) |
GPT-5.6 Sol (max) |
Claude Opus 4.8 (max) |
GPT-5.5 (xhigh) |
GLM-5.2 (max) |
| Reasoning & Knowledge |
| GPQA Diamond |
93.5 |
92.6 |
94.1 |
91.0 |
93.5 |
91.2 |
| CritPt |
23.4 |
28.6 |
32.3 |
20.9 |
27.1 |
20.9 |
| AA-LCR |
74.7 |
70.0 |
73.7 |
67.7 |
74.3 |
71.3 |
| HLE-Full |
43.5 / 56.0 |
53.3 / 63.0 |
44.5 / 58.0 |
49.8 / 57.9 |
41.4 / 52.2 |
— |
| Coding |
| DeepSWE |
67.5 |
70.0 |
73.0 |
59.0 |
67.0 |
46.2 |
| ProgramBench |
77.8 |
76.8 |
77.6 |
71.9 |
70.8 |
63.7 |
| Terminal-Bench 2.1 |
88.3 |
88.0 |
88.8 |
84.6 |
83.4 |
82.7 |
| FrontierSWE |
81.2 |
86.6 |
71.3 |
66.7 |
64.9 |
67.3 |
| SWE-Marathon |
42.0 |
35.0 |
39.0 |
40.0 |
14.0 |
13.0 |
| PostTrainBench |
36.6 |
41.4 |
34.6 |
34.1 |
28.4 |
34.3 |
| MLS-Bench-Lite |
48.3 |
49.9 |
46.2 |
42.8 |
35.5 |
40.4 |
| SciCode |
58.7 |
60.2 |
56.1 |
53.5 |
56.1 |
50.5 |
| Kimi Code Bench 2.0 |
72.9 |
76.9 |
64.8 |
71.7 |
69.0 |
64.2 |
| Agentic |
| BrowseComp |
91.2 |
88.0 |
90.4 |
84.3 |
84.4 |
— |
| DeepSearchQA (F1) |
95.0 |
94.2 |
— |
93.1 |
— |
— |
| ResearchRubrics |
76.2 |
— |
73.8 |
73.5 |
64.0 |
71.1 |
| GDPval-AA v2 (Elo) |
1686 |
1747 |
1736 |
1593 |
1491 |
1510 |
| Toolathlon-Verified |
76.5 |
77.9 |
74.9 |
76.2 |
73.5 |
59.9 |
| MCPMark-Verified |
94.5 |
87.4 |
92.9 |
76.4 |
92.9 |
— |
| MCP-Atlas |