xAI: Grok 4.1 Fast

Provided by OpenRouter

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)

Specifications

Context Length
2,000,000 tokens
Input Price
$0.200/M
Output Price
$0.500/M
Vision Support
Yes
Capabilities
TextVisionFast

About xAI: 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)

Strengths

  • Multimodal understanding - can process text and images
  • Large context window (2000k tokens) for long conversations
  • Fast response times for real-time interactions

Use Cases

  • Image and document understanding
  • Content creation and writing assistance
  • General conversations and Q&A

Limitations

Performance may vary based on query complexity, context length, and task type. Consider using higher-tier models for production-critical applications.

Sample Prompts

Try these prompts to explore xAI: Grok 4.1 Fast's capabilities:

Analyze this image and describe what you see in detail

Extract the key information from this screenshot

Compare the two images and explain the differences

Tip: Customize these prompts to fit your specific needs and use cases.

Premium Model

This model requires credits to use. xAI: Grok 4.1 Fast offers advanced capabilities and high-performance features for production-grade applications.

Credits required for premium models. Free models are available without credits.

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