x-aimodel

xAI: Grok 4 Fast

Grok 4 Fast is xAI's latest multimodal model with SOTA cost-efficiency and a 2M token context window. It comes in two flavors: non-reasoning and reasoning. Read more about the model...

text vision multimodal reasoning cheap long-context

Best for

Image UnderstandingVisual Q&AOCRMultimodal Tasks

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Context Window

2000K tokens ≈ 4.4K pages

Input Cost

$0.20/1M

Output Cost

$0.50/1M

Latency p50

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Pricing Details

Standard Pricing

Input (per 1M tokens)

$0.20

Output (per 1M tokens)

$0.50

Price history

5/15/2026$0.20 in / $0.50 out

5/14/2026$0.20 in / $0.50 out

Hallucination Score™ (est.)

Community reliability estimate · not official

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Not yet rated

About this score: Community-estimated based on user reports and publicly available benchmark data (e.g. TruthfulQA). This is not an official score from the model provider. Scores may be inaccurate — always verify with the official leaderboard before making production decisions.

Price HistoryPro

Input & output cost per 1M tokens over time

Price history is a Pro feature

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Provider

x-ai

Usage & Examples

Learn how to use xAI: Grok 4 Fast

✓Complex reasoning and analysis

✓Customer support automation

✓Content generation and editing

✓Code review and debugging

✓Research summarization

💡 Tip: Start with the sample prompts above to see how xAI: Grok 4 Fast works best.

Community Prompts

Proven prompts shared by the community for this model

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