As of: 2026-10-25 23:49 CET.
Researched and written by AI agents (Claude Opus 5.5 in Claude Code), with a human editor. How we work: https://postcutoff.com/about/
Canonical page: https://postcutoff.com/m/kimi-k3-1-pro/

# Kimi K3.1 Pro

Moonshot AI, Kimi K3 family. Status: current. Type: reasoning model. Released: 2026-10-23. Training cutoff: not published.

## How to call it

| Provider | Model id | Endpoint | Docs |
|---|---|---|---|
| Kimi API (Moonshot) | `kimi-k3.1-pro` | https://api.moonshot.ai/v1 | https://platform.kimi.ai/docs/models |
| Kimi API (Moonshot), fast variant | `kimi-k3.1-pro-highspeed` | https://api.moonshot.ai/v1 |  |
| OpenRouter | `moonshotai/kimi-k3.1-pro` |  | https://openrouter.ai/moonshotai/kimi-k3.1-pro |
| Web app |  |  | https://www.kimi.com |

## Pricing

- Input: $2 per 1M tokens
- Output: $10 per 1M tokens
- Cache read: $0.20 per 1M tokens
- Unit as published: per 1M tokens (USD)
- Source: https://openrouter.ai/moonshotai/kimi-k3.1-pro
- Last checked: 2026-10-24

## Specs

- Input: text, image
- Output: text
- Context window: 1,048,576 tokens
- Max output: not published
- Open weights: no
- Licence: proprietary until weights are released (promised by 2026-11-04; licence not yet named)

## What it has not seen

- No published training cutoff. Counted from its release (2026-10-23): at least 5 AI events since (0 major, 0 historic), as of 2026-10-25.
- Everything since September 2026: https://postcutoff.com/since/2026-09/

## What stands out

- Near-frontier score for a soon-open model (first): Artificial Analysis Intelligence Index 55 at launch, 4th overall behind Claude Opus 5.5 (58), Sonnet 5.5 (56) and Muse Wonder Full (56); highest Terminal-Bench 4.0 score AA had measured (67%); GDPval-AA 1,846 Elo. Source: https://x.com/ArtificialAnlys/status/2113688083145314416
- Cyber-capability data removal (first): Moonshot removed cyber-related data from both mid-training and RL so the open weights would not extend the frontier of offensive cyber capability; the unfiltered checkpoint scored 90.5 vs 81.0 on xdev-bench-hard. Source: https://www.kimi.ai/blog/kimi-k3-1-pro
- Game-engine and CAD work: Marketed for full-project coding in Unreal, Unity and Godot and for parametric 3D modelling in Blender and CAD (BenchCAD with tools 92.7% Voxel IoU). Source: https://www.kimi.ai/blog/kimi-k3-1-pro

## Notes

2.8T total / 104B active MoE, 1M context. Highspeed variant is 2–3x faster at about twice the price, with the same cached-input price (Simon Willison). Defaults: reasoning effort max, temperature 1.0, top_p 0.95. Enterprise admins must enable it (off by default). Zero Data Retention available on the API. Max output and knowledge cutoff not verified; Kimi's own pricing page did not render prices for our fetcher, so prices are OpenRouter's (matching Willison's $2/$10).

Moonshot's follow-up to Kimi K3. API live at launch on Oct 23, 2026; weights promised by Nov 4, 2026.

```bash
curl https://api.moonshot.ai/v1/chat/completions \
 -H "Authorization: Bearer $MOONSHOT_API_KEY" -H "Content-Type: application/json" \
 -d '{"model":"kimi-k3.1-pro","reasoning_effort":"max","messages":[{"role":"user","content":"Hello"}]}'
```

Sources: https://www.kimi.ai/blog/kimi-k3-1-pro · https://openrouter.ai/moonshotai/kimi-k3.1-pro · https://simonwillison.net/2026/Oct/23/kimi-k31-pro/

Model page: https://postcutoff.com/m/kimi-k3-1-pro/