grok-4-fast-reasoning

2025-09-19
Chat, Reasoning, Vision
By Grok
Budget Friendly

Input: ￥1.60 / M tokens Output: ￥4.00 / M tokens
Features: Function Calling, Image Input, Image Output, Reasoning, Streaming, Structured Outputs, Text Input, Text Output, Web Search
Context Window: 2M
Maximum Output: 2M

Input: ￥1.60 / M tokens Output: ￥4.00 / M tokens
Features: Function Calling, Image Input, Image Output, Reasoning, Streaming, Structured Outputs, Text Input, Text Output, Web Search
Context Window: 2M
Maximum Output: 2M

Model Description

We’re excited to release grok-4-fast, xAI latest advancement in cost-efficient reasoning models.

Contains two latest models, codenamed:

grok-4-fast-reasoning
grok-4-fast-noreasoning

🔔How to Use

graph LR A("Purchase Now") --> B["Start Chat on Homepage"] A --> D["Read API Documentation"] B --> C["Register / Login"] C --> E["Enter Key"] D --> F["Enter Endpoint & Key"] E --> G("Start Using") F --> G style A fill:#f9f9f9,stroke:#333,stroke-width:1px style B fill:#f9f9f9,stroke:#333,stroke-width:1px style C fill:#f9f9f9,stroke:#333,stroke-width:1px style D fill:#f9f9f9,stroke:#333,stroke-width:1px style E fill:#f9f9f9,stroke:#333,stroke-width:1px style F fill:#f9f9f9,stroke:#333,stroke-width:1px style G fill:#f9f9f9,stroke:#333,stroke-width:1px

Purchase Now

Start Chat on Homepage

Enter Key

Read API Documentation

Enter Endpoint & Key

Start Using

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