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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...
Best for
Image UnderstandingVisual Q&AOCRMultimodal Tasks
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
4/18/2026$0.20 in / $0.50 out
4/17/2026$0.20 in / $0.50 out
4/16/2026$0.20 in / $0.50 out
4/16/2026$0.20 in / $0.50 out
4/16/2026$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
Track pricing trends and catch price drops early.
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Community Prompts
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