xAI

Grok 4.1 Fast (Reasoning)

xAI's fast agentic tool-calling model with a 2M context window and built-in reasoning

xai/grok-4.1-fast-reasoning

Context

Output

30K

Released

2025-11-19

Knowledge cutoff

—

Types

InputTextImage

OutputText

Reasoning

Supported

Tool use

Supported

Structured output

Supported

Attachments

Supported

Open weights

—

Provider pricing

Vertex

InTextImage

OutText

Price: $0.20 / $0.50
Context: 128K
Status: deprecated

Poe

InTextImage

OutText

Price: —
Context: 2M
Status: Stable

Provider	Types	Price	Context	Status
Vertex	InTextImage OutText	$0.20 / $0.50	128K	deprecated
Poe	InTextImage OutText	—	2M	Stable

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