Grok 4.1 Fast
xAI's low-cost fast lane for tool-calling agents, web retrieval, and research-heavy workflows.
Pricing
Input$0.20 / 1M
Cached input$0.05 / 1M
Output$0.50 / 1M
Tool calls start at $5 / 1,000 successful invocations.
Cost bandBudget-balanced
Free tierNo free API tier.
Limits
Context window2M
Max outputSee docs
Knowledge cutoffNot surfaced in source summary
DeploymentxAI API
OpenAI-compatible APIYes
ModalitiesText
Where it fits
Best forAgentic research, search workflows, and teams that want xAI's web-native strengths at low price.
Business fitOne of the more aggressive managed reasoning prices in the frontier tier.
Capabilities
ReasoningTool useWeb browseX searchCode executionDocument retrieval
Benchmark scores
Composite82 / 100
Coding84 / 100 (SWE-bench Verified)
Reasoning83 / 100 (GPQA Diamond)
Long context81 / 100 (RULER 2M)
Vision73 / 100 (MMMU)
Instruction following85 / 100 (IFEval)
Editorial aggregate of published benchmark results as of Dec 1, 2025. These are not independent measurements run by this site.
Change history
- Jul 19, 2026DeprecatedGrok 4.1 Fast retired No longer listed on xAI's model and pricing pages as of Jul 19, 2026. Current xAI lineup: Grok 4.5, 4.3, and 4.20. xAI models and pricing
- Dec 20, 2025New modelGrok 4.1 Fast released 2M context at $0.20/$0.50 per 1M — aggressive frontier pricing with reasoning and web-native tools.
Data
Last checkedMar 31, 2026
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