Overview
Kimi K3.1 Pro is the first model in Moonshot AI's K3.1 series, released on October 23, 2026. It is a post-trained version of Kimi K3 that received substantially more post-training compute, and Moonshot describes it as its most capable 3T-class model. It runs with a 1M-token context window. A Kimi K3.1 Pro Highspeed variant offers the same capabilities at 2-3x the speed.
Moonshot trained K3.1 Pro with joint reinforcement learning across hundreds of domains, after improving its RL framework, long-context inference, sandbox infrastructure, rollout scheduling and environment quality checks. The launch post focuses on long-horizon coding (including Unity, Unreal Engine and Godot projects), scripting 3D and CAD tools such as Blender, and finance and business work.
At launch the model is served on Kimi.ai, the Kimi mobile apps, Kimi Work (desktop 3.1.0 or later), Kimi Code and the Kimi API under the model IDs kimi-k3.1-pro and kimi-k3.1-pro-highspeed. Moonshot removed cyber-related data from mid-training and RL before the planned open-weight release, and promised full weights by November 4, 2026.
| Released | 2026-10-23 |
|---|---|
| License | Not stated at launch (open weights promised by 2026-11-04) |
| Weights | API only |
| Parameters | 3T-class (exact count not published) |
| Context | 1M |
| Modalities | Text |
| Status | Generally available |
Benchmarks
- Terminal-Bench 4.065.7%
- Kimi Code Bench 3.0 Long-horizon61.2%
- BenchCAD Voxel IoU (with tools)92.7%
- OfficeQA Pro v264.4%
Scores on a 0–100 scale (25-point gridlines); higher is better. Each benchmark links to its published source.
Strengths
- 65.7% on Terminal-Bench 4.0 in Moonshot's launch table, next to Claude Opus 5.5 (66.4%)
- Claim-level hallucination rate on Kimi Hallu Bench Hard (with tools) cut from 23.4% for K3 to 8.3%
- Scripts 3D and CAD tools: 92.7 Voxel IoU on BenchCAD with tools
- 1M-token context with a 2-3x faster Highspeed variant
Best for
- Reach for it for long-horizon coding agents, including game-engine projects in Unity, Unreal Engine or Godot.
- Reach for it when an agent must write and run scripts for Blender or CAD software.
- Reach for it for finance and business-operations tasks inside Kimi Work.
How to access
| Provider | Model ID |
|---|---|
| Kimi API (Moonshot) ↗ | kimi-k3.1-pro |
Kimi K3 — every version
The full lineage of the Kimi K3 line, newest first. Every version has its own page — click any to compare specs, benchmarks and pricing.
| Version | Released | Context | License |
|---|---|---|---|
| Kimi K3.1 Procurrent | 2026-10-23 | 1M | — |
| Kimi K3 | 2026-07-16 | 1M | Kimi K3 License |
FAQ
When will Kimi K3.1 Pro weights be released?
Moonshot AI promised full Kimi K3.1 Pro weights by November 4, 2026. At the October 23, 2026 launch the model was available only through Kimi.ai, the Kimi apps, Kimi Work, Kimi Code and the Kimi API, and the license was not yet stated.
What is Kimi K3.1 Pro Highspeed?
Kimi K3.1 Pro Highspeed is a variant of Kimi K3.1 Pro that runs at 2-3x the speed with the same capabilities. On the Kimi API it uses the model ID kimi-k3.1-pro-highspeed.
How is Kimi K3.1 Pro different from Kimi K3?
Kimi K3.1 Pro is Kimi K3 with substantially more post-training compute and joint RL across hundreds of domains. Moonshot reports gains such as 61.2% vs 55.95% on its long-horizon Kimi Code Bench 3.0 and a hard-benchmark hallucination rate of 8.3% vs 23.4%.