Grok-4.1-Fast-Reasoning

Grok-4.1-Fast-Reasoning is a frontier multimodal model designed from the ground up for high-performance, agentic execution. Rather than serving as a general-purpose chatbot, it prioritizes complex task completion through strong reasoning, advanced tool calling, and agentic search capabilities. The architecture emphasizes low-latency responses while maintaining the intelligence needed to handle nuanced, multi-step workflows. It supports both text and image inputs, making it versatile for real-world applications ranging from customer support automation to financial analysis, where precision and speed matter equally.

The model positions itself among the more intelligent models available, scoring 39 on the Artificial Analysis Intelligence Index—well above the comparable average of 21—while maintaining pricing that remains reasonable relative to its performance tier. Its token output speed of 122 tokens per second outpaces the typical average of 105, reflecting its design focus on responsiveness in agentic pipelines. The emphasis on tool calling and agentic search makes it particularly well-suited for developers building production-grade agents that need to orchestrate external actions and retrieve information dynamically rather than simply generating static responses.

Poexai/grok-4.1-fast-reasoninggrok

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Quick Info

Provider: Poe
Model key: xai/grok-4.1-fast-reasoning
Release date: Nov 19, 2025
Last updated: Nov 19, 2025
Input modalities
Output modalities
Capabilities

Limits

Output tokens: 30,000 tokens
Context window: 2,000,000 tokens

Latest news about Grok-4.1-Fast-Reasoning

Poe

CoverageBenchmark

The BenchLM.ai model record for "Grok 4.1 Fast (Reasoning)" lists a release date of November 19, 2025, a proprietary license, reasoning capability, and a 2M-token context window, with the model attributed to xAI as creator. It assigns a composite score of 58.2 out of 100 and a rank of 82 out of 232 tracked models, with Capability shape data on the page shows the model is rank-eligible only in the Coding category, with other axes marked not eligible, and does not include measurements for price, output speed, or time-to-first-token. Data is reported as of September 4, 2026, positioning Grok 4.1 Fast (Reasoning) as a software-developmen

Poe

CoverageBenchmark

The madebyagents.com family leaderboard for xAI's Grok catalog lists "Grok 4.1 Fast Reasoning" as a discrete entry with a composite score of 63.2, released November 18, 2025, and accessible via xAI's API. It places the Reasoning variant within the broader Grok release timeline alongside Grok 4.1 (Thinking), Grok 4.1, a Family-level quick facts indicate an average score of 67.2 across the catalog and a top benchmark of 99.2 on MATH-500, with context windows ranging from 131K to 2.0M and text as the primary modality across 17 tracked models. As an aggregator page rather than a primary source, the entry is useful for confirming that the