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    grok-4-fast

    grok/grok-4-fast

    ChatVisionToolsSystem promptReasoning
    Use this model

    Context

    2M

    Max output

    64K

    Input / 1M

    $0.20

    Output / 1M

    $0.50

    Modality

    Chat

    Cutoff

    Oct 2023

    About this model

    Grok Models

    Best suited for

    • Real-time data extraction, rapid Q&A, tool-augmented tasks, and enterprise applications needing speed, cost efficiency, and high-throughput performance.

    Built-in tools

    Gtwy web search

    Hosted by the gateway — enable them per request without wiring your own endpoint.

    Capabilities

    Vision

    Accepts images alongside text in the same message.

    Tools

    Native function calling, so agents can invoke your endpoints.

    System prompt

    Honours a dedicated system role, separate from the user turn.

    Reasoning

    Emits a separate thinking pass before the answer.

    Supported parameters

    creativity_level

    Controls the creativity of responses. Higher values (e.g., 0.7) increase creativity; lower values (e.g., 0.2) make responses more predictable.

    max_tokensMax Tokens Limit

    Specifies the maximum number of text units (tokens) allowed in a response, limiting its length.

    tools

    Lists tool definitions or capabilities available to the model.

    tool_choice

    Decides whether to use tools or just the model for generating responses.

    response_type

    Defines the format or type of the generated response.

    parallel_tool_calls

    Enables parallel execution of tools, allowing multiple tools to run simultaneously.

    reasoning

    Controls the level of reasoning used by the model.

    stream

    Sends the response in real-time as it's being generated.

    Use this model

    OpenAI-SDK compatible, with gateway fallback and routing across providers.

    Other Grok models

    ModelContextMax outputInputOutputCapabilities
    grok-4-0709

    Chat

    		2M64K$0.20$0.50Vision, Tools, System prompt, Reasoning
    grok-4-fast-reasoning

    Chat

    		2M64K$0.25$0.60Tools, System prompt, Reasoning

    Pricing & provider details

    Grok logo

    Grok

    grok/grok-4-fast

    Input · per 1M
    $0.20
    Output · per 1M
    $0.50
    Cached input · per 1M
    —
    Context window
    2,000,000 tokens
    Max output
    64,000 tokens
    Knowledge cutoff
    Oct 2023
    Auto-router
    Not supported

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    Route grok-4-fast — and every other model in the catalogue — through one endpoint, with failover built in.

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