# Kimi K3.1 Pro Kimi K3.1 Pro is Moonshot AI's flagship open-weight multimodal reasoning model, a post-trained successor to Kimi K3 built for long-horizon coding, 3D creation, financial research and agentic knowledge work. It always reasons, with a selectable effort level, and is the first model in the K3.1 series. Its published context window is 1,048,576 tokens. The advertised input rate is $2.00 per million input tokens. The advertised output rate is $10.00 per million output tokens. - Model identifier: ` moonshotai/kimi-k3.1-pro ` - Creator: Moonshot AI - Providers: Moonshot AI - Model type: Text generation - Canonical model page: [Kimi K3.1 Pro]() - API availability: Listed as serving through Impossibl. - Creator release date: 2026-10-23 ## Providers Moonshot AI hosts Kimi K3.1 Pro. Impossibl routes your request intelligently and handles failover automatically when a provider is down. | Provider | Endpoint location | Routes | Verified context window | Tool calling | | --- | --- | --- | --- | --- | | Moonshot AI | Not specified | 1 | Not verified | Not verified | The model price applies whichever provider serves the request. Endpoint locations do not guarantee inference residency. ## Specs and Capabilities - Context window: 1,048,576 tokens - Maximum output tokens: Not published in the public catalog; this is separate from the context window. - Inputs: text, image - Outputs: text - Tool calling: Not published ## API access Use ` moonshotai/kimi-k3.1-pro ` as the model identifier through the Impossibl API. Published API endpoints: - ` /v1/chat/completions ` [API quickstart]() · [Models and billing documentation]() ## Published API prices All rates are in USD. An unpublished rate is unknown, not zero. Workspace-specific pricing, taxes, balance-purchase fees, billing adjustments, and tool charges can affect the amount paid. | Usage | Published base rate | Billing unit | | --- | --- | --- | | Input | $2.00 | per million input tokens | | Output | $10.00 | per million output tokens | | Cache read | $0.20 | per million cached input tokens | | Cache write (default retention) | Not published | per million tokens | | Cache write (one-hour retention) | Not published | per million tokens | | Audio input | Not published | per million audio input tokens | ## Benchmarks Last checked: 2026-10-23T19:30:16.329Z. Configurations are evaluated separately. API scores retain their original units. Unmeasured scores are omitted. ### Kimi K3.1 Pro Source: [Evaluation source]() | Benchmark | Score | | --- | --- | | Intelligence Index | 55.09 | | Omniscience Index | 29.52 | | Humanity’s Last Exam | 52.46% | | SciCode | 60.76% | | CritPt | 24.57% | | AA-LCR | 86.33% | | GDPval Elo | 1845.72 | | GDP.pdf All-pass | 31.40% | | AutomationBench Partial | 73.30% | | MMMU-Pro | 83.87% | | legal index (API) | 55.8 | | economics index (API) | 60 | | engineering index (API) | 55.9 | | intelligence index (API) | 55.1 | | strategy and ops index (API) | 59.4 | | finance and accounting index (API) | 56.5 | Full benchmark data and breakdowns: [Complete benchmark snapshot](). ## Availability and retirement The model is listed as serving. No retirement is announced in the current public catalog. ## Frequently asked questions ### What is Kimi K3.1 Pro? Kimi K3.1 Pro is Moonshot AI's flagship open-weight multimodal reasoning model, a post-trained successor to Kimi K3 built for long-horizon coding, 3D creation, financial research and agentic knowledge work. It always reasons, with a selectable effort level, and is the first model in the K3.1 series. Sources: [Kimi K3.1 Pro announcement](); [Kimi K3.1 Pro quickstart](); [OpenRouter model listing](); [Unite.AI release coverage]() ### How much does Kimi K3.1 Pro cost? Kimi K3.1 Pro costs $2.00 per million input tokens and $10.00 per million output tokens through the Impossibl API. Cache reads cost $0.20 per million tokens. All rates are in USD. ### What is the context length of Kimi K3.1 Pro? Kimi K3.1 Pro has a 1,048,576-token context window through the Impossibl API. ### What inputs and outputs does Kimi K3.1 Pro support? Kimi K3.1 Pro accepts text and image as input. Kimi K3.1 Pro returns text. ### How do I use Kimi K3.1 Pro through an API? Kimi K3.1 Pro is available through the Impossibl API. Use moonshotai/kimi-k3.1-pro as the model identifier with /v1/chat/completions. The quickstart explains how to create an API key and send your first request. ### When was Kimi K3.1 Pro released? Moonshot AI released Kimi K3.1 Pro on October 23, 2026. Sources: [Creator release announcement]() ## Sources and related links Prices, limits, capabilities, endpoints, and availability come from the public Impossibl catalog. Creator documentation supplies descriptions and release dates where available; it does not override the published API offering. - [Public Impossibl model catalog]() - [Full model directory as JSON]() - [Kimi K3.1 Pro: model details and pricing]() - [Model directory]() - [Kimi K3.1 Pro announcement]() - [Kimi K3.1 Pro quickstart]() - [OpenRouter model listing]() - [Unite.AI release coverage]()