All Models
Grok 4.1 Fast
Grok 4.1 Fast is xAI's best agentic tool calling model that shines in real-world use cases like customer support and deep research. 2M context window. Reasoning can be enabled/disabled using the `reasoning` `enabled` parameter in the API. [Learn more in our docs](https://openrouter.ai/docs/use-cases/reasoning-tokens#controlling-reasoning-tokens)
Available Providers (5)
| Provider | Model ID | Input Cost | Output Cost | Context | Max Output | Docs |
|---|---|---|---|---|---|---|
 ZenMux | x-ai/grok-4.1-fast | $0.20/MTok | $0.50/MTok | 2M | 64K | |
 OpenRouter | x-ai/grok-4.1-fast | $0.20/MTok | $0.50/MTok | 2M | 30K | |
 NanoGPT | x-ai/grok-4.1-fast | $0.20/MTok | $0.50/MTok | 2M | 131.1K | |
 xAI | grok-4-1-fast | $0.20/MTok | $0.50/MTok | 2M | 30K | |
 Venice AI | grok-41-fast | $0.25/MTok | $0.63/MTok | 1M | 30K |
Capabilities
Reasoning
Tool Calling
Attachments
Open Weights
Structured Output