Gemini 3.7 Flash vs Grok-4 Fast Reasoning
Comparing Gemini 3.7 Flash and Grok-4 Fast Reasoning across benchmarks, pricing, and capabilities.
Google · xAI · Updated for 2026
Which is better?
Gemini 3.7 Flash and Grok-4 Fast Reasoning trade strengths across price, capabilities, and technical limits. The better choice depends on the workload.
On price, Grok-4 Fast Reasoning is roughly 5.5x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.
Grok-4 Fast Reasoning also accepts a larger context window (2,000,000 input tokens), making it the stronger choice for long documents and large codebases.
Based on current benchmark, pricing, and model metadata for 2026.
Choose Gemini 3.7 Flash
- you want the most recent training data — it shipped Aug 2026
Choose Grok-4 Fast Reasoning
- cost matters — it's about 5.5x cheaper per token
- you process long inputs — it offers a 2,000,000 token context window
At a glance
The differences that matter most.
Performance Benchmarks
Comparative analysis across standard metrics
Gemini 3.7 Flash and Grok-4 Fast Reasoningdon't have any common benchmark datasets to compare. They may have been evaluated on different testing suites.
Arena Performance
Playground indexes and blind preference scores
Pricing Analysis
Price comparison per million tokens
For input processing, Gemini 3.7 Flash ($0.75/1M tokens) is 3.8x more expensive than Grok-4 Fast Reasoning ($0.20/1M tokens).
For output processing, Gemini 3.7 Flash ($3.75/1M tokens) is 7.5x more expensive than Grok-4 Fast Reasoning ($0.50/1M tokens).
In conclusion, Gemini 3.7 Flash 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 Gemini 3.7 Flash's 1,048,576 tokens. Gemini 3.7 Flash can generate longer responses up to 65,536 tokens, while Grok-4 Fast Reasoning is limited to 30,000 tokens.
Input Capabilities
Supported data types and modalities
Both Gemini 3.7 Flash and Grok-4 Fast Reasoning support multimodal inputs.
They are both capable of processing various types of data, offering versatility in application.
Gemini 3.7 Flash
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
Gemini 3.7 Flash was released on 2026-08-13, while Grok-4 Fast Reasoning was released on 2025-08-28.
Gemini 3.7 Flash is 12 months newer than Grok-4 Fast Reasoning.
Aug 13, 2026
1 weeks ago
11mo newerAug 28, 2025
12 months ago
Knowledge Cutoff
When training data ends
Gemini 3.7 Flash has a documented knowledge cutoff of 2026-03-31, while Grok-4 Fast Reasoning's cutoff date is not specified.
We can confirm Gemini 3.7 Flash's training data extends to 2026-03-31, but cannot make a direct comparison without Grok-4 Fast Reasoning's cutoff date.
Mar 2026
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Provider Availability
Gemini 3.7 Flash is available from Google. Grok-4 Fast Reasoning is available from xAI.
Gemini 3.7 Flash
Grok-4 Fast Reasoning
Outputs Comparison
Judge for yourself.
Run your own prompts against Gemini 3.7 Flash and Grok-4 Fast Reasoning side-by-side, then vote on the output you prefer.
FAQ
Common questions about Gemini 3.7 Flash vs Grok-4 Fast Reasoning.