All Models

X-Ai/Grok-4-Fast-Reasoning

Reasoning Tool Calling Attachments
Providers 1
Released Dec 18, 2025
Input Modalities text, image, audio, video
Output Modalities text
Tarsk Use coding

Benchmarks

35.1
Intelligence Index
27.4
Coding Index
89.7
Math Index

Available Providers (1)

Provider Model ID Input Cost Output Cost Context Max Output Docs
Qiniu x-ai/grok-4-fast-reasoning —/MTok —/MTok 2M 2M

Capabilities

Reasoning
Tool Calling
Attachments
Open Weights
Structured Output