# Introducing Kimi K3.1 Pro

> Source: <https://simonwillison.net/2026/Oct/23/kimi-k31-pro/>
> Published: 2026-10-23 19:40:54+00:00

They're also offering a "Highspeed" version that's 2-3x faster, at twice the price (except for input token cache hits, which are priced the same).

The [US dollar pricing](https://platform.kimi.ai/docs/pricing/chat) is $2.00/million tokens for input and $10/million for output - the same as GPT-6.1 Sol and half the price of Claude Opus 5.5.

Moonshot's own benchmarks show Kimi as approximately level with Opus 5.5 and GPT-6 Astra - beating them on a few benchmarks, coming close on others.

Artificial Analysis [scored Kimi at 55](https://artificialanalysis.ai/models/kimi-k3-1-pro) - ahead of Claude Fable 5.1, GPT-6 Astra, and Gemini 4 Argon (all at 53) and behind only Claude Opus 5.5 (58).

This is the first time a (soon-to-be) open weight model has scored this highly against the frontier.

I tried it out via the [Moonshot API](https://platform.kimi.ai/docs/get-your-api-key) using the [llm openai endpoint](https://llm.datasette.io/en/stable/other-models.html#openai-endpoint) command I added to [LLM 0.32](https://llm.datasette.io/en/stable/changelog.html#v0-32) back in August:

```
llm openai endpoint \
  https://api.moonshot.ai/v1 \
  --key kimi \
  -m kimi-k3.1-pro \
  "Generate an SVG of a pelican riding a bicycle" \
  --responses \
  -o reasoning_effort low \
  > kimi-k3.1-pro-pelican-low.stdout.txt \
  2> kimi-k3.1-pro-pelican-low.stderr.txt
```

`llm openai endpoint` can run prompts against any OpenAI-compatible endpoint but doesn't log the results, hence the extra options to save stdout and stderr (the reasoning trace).

Here [are the pelicans](https://tools.simonwillison.net/markdown-svg-renderer?url=https%3A%2F%2Fgist.github.com%2Fsimonw%2F9b7181492209387da1d4f53002f26663) I got for Kimi K3.1 Pro on the three reasoning levels it supports -  low, medium, and max. This is max:

For comparison, I ran fresh [pelicans against Kimi K3](https://tools.simonwillison.net/markdown-svg-renderer?url=https%3A%2F%2Fgist.github.com%2Fsimonw%2Feba9a4283c9e94cbbb5325902a3921a8) on those three reasoning levels.
    

Via [Hacker News](https://news.ycombinator.com/item?id=50212065)

Tags: [ai](https://simonwillison.net/tags/ai), [generative-ai](https://simonwillison.net/tags/generative-ai), [llms](https://simonwillison.net/tags/llms), [llm](https://simonwillison.net/tags/llm), [llm-pricing](https://simonwillison.net/tags/llm-pricing), [pelican-riding-a-bicycle](https://simonwillison.net/tags/pelican-riding-a-bicycle), [llm-release](https://simonwillison.net/tags/llm-release), [ai-in-china](https://simonwillison.net/tags/ai-in-china), [moonshot](https://simonwillison.net/tags/moonshot), [kimi](https://simonwillison.net/tags/kimi)