Kimi K3.1 Pro

by Moonshot AI

Kimi K3.1 Pro is Moonshot AI's post-trained successor to Kimi K3: a 2.8-trillion-parameter mixture-of-experts model with 104B parameters active per token. Moonshot reports gains over K3 in coding, factual accuracy, and long-horizon agentic work. It accepts images, calls tools, reasons by default with adjustable effort, and has a 1,048,576-token context window.

Best for: Frontier open-weight coding agents that run for hours on a million-token context.

1M context

Text
Reasoning
Tool use
Image input
Vision

Model weights

Try it in the playground

Pricing

USD per 1M tokens.

Provider	Input	Cached input	Output
Boundless	$1.70	$0.20	$8.50

What one request costs

Prompt94Ktokens

Cached prefix66Ktokens

Reply2Ktokens

$0.0739

per request to Kimi K3.1 Pro

Prompt: 64.9%
Cached: 17.8%
Reply: 17.3%

The same request, across other models