Grok 4 Fast ReasoningDeprecated
Benchmarks
independent evaluations · source: ARC Prize and Artificial Analysis| Benchmark | Best score | Effort | Cost / task | |
|---|---|---|---|---|
| ARC-AGI-2 | 5% | default | $0.061 | |
| CritPt | 3% | default | — | |
| GPQA Diamond | 85% | default | — | |
| Humanity's Last Exam | 19% | default | — | |
| IFBench | 51% | default | — | |
| LiveCodeBench | 83% | default | — | |
| Long-Context Reasoning | 74% | default | — | |
| MMLU-ProFrozen Aug 18, 2026 | 85% | default | — | |
| MMMU-Pro | 62% | default | — | |
| Omniscience | -29.9 | default | — | |
| Omniscience Accuracy | 0.2 | default | — | |
| Omniscience Non Hallucination | 0.3 | default | — | |
| SciCodeArtificial Analysis did not report this score in its latest run on Oct 14, 2026 | 44% | — | — | |
| TerminalBench Hard | 19% | default | — | |
| τ²-bench | 66% | default | — |
Pricing by serving provider
standard tier · per 1M tokens · click a provider to expandInput pricing runs from $0.20 to $1.25 per 1M tokens across 2 providers, so the dearest route costs 525% more than the cheapest for the same model.
| Serving provider | Input /1M | Output /1M | Endpoints | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| AzureCheapest | $0.20 | $0.50 | 1 | |||||||||||||
Standardazure_ai/grok-4-fast-reasoning
| ||||||||||||||||
| xAI | $1.25 | $2.50 | 1 | |||||||||||||
Standardxai/grok-4-fast-reasoning
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Price history
listed seller prices, input and output per 1M tokensCost calculator
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copy the exact identifier for your platformFrequently asked questions
Grok 4 Fast Reasoning pricing, context and availabilityIs Grok 4 Fast Reasoning still available?
Grok 4 Fast Reasoning was deprecated on 2026-05-01, but 2 serving providers still list it.
How much does Grok 4 Fast Reasoning cost?
Grok 4 Fast Reasoning costs $0.20 per 1M input tokens from Azure, and $0.50 per 1M output tokens from Azure. Across 2 serving providers, input prices range from $0.20 to $1.25 per 1M tokens.
What is the context window of Grok 4 Fast Reasoning?
Grok 4 Fast Reasoning accepts up to 2M tokens of context and can return up to 2M output tokens.
Which providers serve Grok 4 Fast Reasoning?
Grok 4 Fast Reasoning is available from 2 serving providers, each with its own pricing and model ID. Azure is currently the cheapest.
What can Grok 4 Fast Reasoning do?
Grok 4 Fast Reasoning supports tool use, prompt caching, structured output and web search.
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