Model Comparison
Grok-3 Mini vs Grok-4 Fast Reasoning
Comparing Grok-3 Mini and Grok-4 Fast Reasoning across benchmarks, pricing, and capabilities.
Performance Benchmarks
Comparative analysis across standard metrics
Grok-3 Mini and Grok-4 Fast Reasoning don't have any common benchmark datasets to compare. They may have been evaluated on different testing suites.
Arena Performance
Human preference votes
Pricing Analysis
Price comparison per million tokens
For input processing, Grok-3 Mini ($0.30/1M tokens) is 1.5x more expensive than Grok-4 Fast Reasoning ($0.20/1M tokens).
For output processing, Grok-3 Mini ($0.50/1M tokens) costs the same as Grok-4 Fast Reasoning ($0.50/1M tokens).
In conclusion, Grok-3 Mini is more expensive than Grok-4 Fast Reasoning.*
* Using a 3:1 ratio of input to output tokens
Context Window
Maximum input and output token capacity
Grok-4 Fast Reasoning accepts 2,000,000 input tokens compared to Grok-3 Mini's 128,000 tokens. Grok-4 Fast Reasoning can generate longer responses up to 30,000 tokens, while Grok-3 Mini is limited to 8,000 tokens.
Input Capabilities
Supported data types and modalities
Both Grok-3 Mini and Grok-4 Fast Reasoning support multimodal inputs.
They are both capable of processing various types of data, offering versatility in application.
Grok-3 Mini
Grok-4 Fast Reasoning
License
Usage and distribution terms
Both models are licensed under proprietary licenses.
Both models have usage restrictions defined by their respective organizations.
Proprietary
Closed source
Proprietary
Closed source
Release Timeline
When each model was launched
Grok-3 Mini was released on 2025-02-17, while Grok-4 Fast Reasoning was released on 2025-08-28.
Grok-4 Fast Reasoning is 6 months newer than Grok-3 Mini.
Feb 17, 2025
1.3 years ago
Aug 28, 2025
8 months ago
6mo newerKnowledge Cutoff
When training data ends
Grok-3 Mini has a documented knowledge cutoff of 2024-11-17, while Grok-4 Fast Reasoning's cutoff date is not specified.
We can confirm Grok-3 Mini's training data extends to 2024-11-17, but cannot make a direct comparison without Grok-4 Fast Reasoning's cutoff date.
Nov 2024
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Provider Availability
Grok-3 Mini is available from xAI. Grok-4 Fast Reasoning is available from xAI.
Grok-3 Mini
Grok-4 Fast Reasoning
Outputs Comparison
Key Takeaways
No standout differentiators in the data we have for this pair.
Grok-3 MiniGrok-4 Fast ReasoningDetailed Comparison
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FAQ
Common questions about Grok-3 Mini vs Grok-4 Fast Reasoning.