Text Generation Model

Grok 3 Mini Fast

Grok 3 Mini Fast is a text generation model from X.ai designed for fast inference with a 131,072 token context window.

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Publisher

X.ai

TypeText

Context Window131,072 tokens

ReleasedApril 2025

Input$0.60/MTok

Output$4.00/MTok

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About Grok 3 Mini Fast

Lightweight reasoning model optimized for speed

Grok 3 Mini Fast is a lightweight text generation model developed by X.ai, released in April 2025 as part of the Grok 3 model family. It operates under the model ID grok-3-mini-fast-beta and is designed to prioritize response speed while maintaining a large context window of 131,072 tokens. The model handles text-based chat and generation tasks and supports a maximum response size of 8,192 tokens per output.

Grok 3 Mini Fast is suited for applications where low latency is a priority, such as real-time assistants, high-throughput pipelines, or tasks that require rapid text generation over long contexts. As the "mini fast" variant in the Grok 3 lineup, it trades some of the capacity of larger models for quicker turnaround times. Developers working within MindStudio can access it directly without managing separate API credentials.

Capabilities

What Grok 3 Mini Fast supports

Large Context Window

Processes up to 131,072 tokens in a single request, enabling long documents, extended conversations, or multi-step instructions within one context.

Fast Text Generation

Optimized for low-latency inference, making it suitable for real-time applications and high-throughput text generation pipelines.

Chat Completion

Supports multi-turn conversational interactions via a standard chat interface, returning up to 8,192 tokens per response.

Reasoning Tasks

Handles instruction-following and reasoning tasks as part of the Grok 3 mini model family, which is designed with chain-of-thought capabilities.

API Integration

Available as a first-party model on MindStudio under the ID grok-3-mini-fast-beta, accessible without separate API key management.

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Performance

Benchmark scores

Scores represent accuracy — the percentage of questions answered correctly on each test.

Benchmark	What it tests	Score
MMLU-Pro	Expert knowledge across 14 academic disciplines	82.8%
GPQA Diamond	PhD-level science questions (biology, physics, chemistry)	79.1%
MATH-500	Undergraduate and competition-level math problems	99.2%
AIME 2024	American math olympiad problems	93.3%
LiveCodeBench	Real-world coding tasks from recent competitions	69.6%
HLE	Questions that challenge frontier models across many domains	11.1%
SciCode	Scientific research coding and numerical methods	40.6%

FAQ

Common questions about Grok 3 Mini Fast

What is the context window size for Grok 3 Mini Fast?

Grok 3 Mini Fast supports a context window of 131,072 tokens, allowing long documents or extended conversations to be processed in a single request.

What is the maximum response length?

The model can generate up to 8,192 tokens per response.

Who publishes Grok 3 Mini Fast?

Grok 3 Mini Fast is published by X.ai and is available as a first-party model on MindStudio.

When was Grok 3 Mini Fast released?

Grok 3 Mini Fast was released in April 2025 under the beta model ID grok-3-mini-fast-beta.

Does Grok 3 Mini Fast support image or video inputs?

Based on the available metadata, Grok 3 Mini Fast is a text-only model. Image and video analysis support is not indicated for this variant.

Is pricing information available for Grok 3 Mini Fast?

Published pricing details are not currently listed in the model metadata. Check X.ai's official documentation or MindStudio's pricing page for the latest information.

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