Kimi K3.1 Pro is Moonshot AI's flagship open-weight multimodal reasoning model and a post-trained successor to Kimi K3, with a 1,048,576-token context window and up to 943,718 output tokens. It accepts text, image, and video input and returns text, and is built for long-horizon coding, agentic tool use, and complex multi-step reasoning. Reasoning is on by default with selectable effort (none / low / high / max), alongside native function calling and structured (JSON) outputs. Available over the Chat Completions, OpenAI Responses, and Anthropic Messages APIs. Artificial Analysis Intelligence Index: 55.1.
OpenAI-compatible — keep the SDK you already use
https://api.orcarouter.ai/v1https://api.orcarouter.aiimport os
from openai import OpenAI
client = OpenAI(
base_url="https://api.orcarouter.ai/v1",
api_key=os.environ["ORCAROUTER_API_KEY"],
)
response = client.chat.completions.create(
model="kimi/kimi-k3.1-pro",
messages=[{"role": "user", "content": "Hello"}],
)
print(response.choices[0].message.content)frequency_penaltyinclude_reasoningmax_tokenspresence_penaltyreasoningreasoning_effortresponse_formatstopstructured_outputstool_choicetools| Input / 1M tokens | $2.00 |
|---|---|
| Output / 1M tokens | $10.00 |
| Cache read / 1M | $0.200 |
| Currency | USD |
Estimate based on list price
Estimate only — actual token counts depend on the provider's tokenizer.
What developers are saying this week
GET /api/public/models/kimi/kimi-k3.1-proOpen @misc{orcarouter_kimi_k3_1_pro,
title = {Kimi K3.1 Pro API},
author = {MoonshotAI},
year = {2026},
howpublished = {OrcaRouter},
url = {https://www.orcarouter.ai/models/kimi/kimi-k3.1-pro}
}MoonshotAI. (2026). Kimi K3.1 Pro API. OrcaRouter. https://www.orcarouter.ai/models/kimi/kimi-k3.1-pro