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grok-4-fast-reasoning

grok family · launched 2025-09-16

MultimodalReasoningTools
AITopic score39.2#94 overall

Fast Grok model for responsive chat, reasoning, and tool-assisted work

Evidence coverage3%1 evaluations · 1 institutions
Context / maximum output2M / 128ktokens
Cache / input / output$0.05 · $0.2 · $0.5USD per million tokens
Value / freshness58.1 / 43relative value · release freshness
Product profile

What this model supports

Inputtext, image
Outputtext
Knowledge cutoffNot disclosed
WeightsProprietary / hosted
Capability profile

Strengths by domain

Coding—0 public results
Research & reasoning—0 public results
Professional work—0 public results
Knowledge & instruction—0 public results
Behind the score

Every result has a source

Raw results and standardized readings are shown together. Missing tests add neither points nor penalties.

Human preference & indices2 results

AA IndexArtificial Analysis59.99 indexReading 39.2

Imported from a directly fetched third-party leaderboard.

Configuration: grok-4-fast-reasoningOpen evidence
Arena TextLMArena1,399.7 EloReading 39.2

Direct LMArena text leaderboard result.

Open evidence
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