Grok 4.1 Fast (Reasoning) vs Step 3.5 Flash: The Ultimate Performance & Pricing Comparison

Deep dive into reasoning, benchmarks, and latency insights.

The Final Verdict in the Grok 4.1 Fast (Reasoning) vs Step 3.5 Flash Showdown

After a comprehensive analysis, Grok 4.1 Fast (Reasoning) emerges as the superior choice for users prioritizing raw intelligence and reasoning. However, Step 3.5 Flash remains a highly competitive option, especially for scenarios demanding faster response times and cost-efficiency. This detailed Grok 4.1 Fast (Reasoning) vs Step 3.5 Flash comparison will break down every critical metric to help you make the best decision.

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Model Snapshot

Key decision metrics at a glance.

Grok 4.1 Fast (Reasoning)

xAI

Reasoning: 9
Coding: 3
Multimodal: 3
Long Context: 5
Blended Price / 1M tokens: $0.000
P95 Latency: 1000ms
Tokens per second: 108.559tokens/sec

Step 3.5 Flash

Other

Reasoning: 6
Coding: 3
Multimodal: 3
Long Context: 5
Blended Price / 1M tokens: $0.000
P95 Latency: 1000ms
Tokens per second: 203.967tokens/sec

Overall Capabilities

The capability radar provides a holistic view of the Grok 4.1 Fast (Reasoning) vs Step 3.5 Flash matchup. This chart illustrates each model's strengths and weaknesses at a glance, forming a cornerstone of our Grok 4.1 Fast (Reasoning) vs Step 3.5 Flash analysis.

This radar chart visually maps the core capabilities (reasoning, coding, math proxy, multimodal, long context) of `Grok 4.1 Fast (Reasoning)` vs `Step 3.5 Flash`.

Benchmark Breakdown

For a granular look, this chart directly compares scores across standardized benchmarks. In the critical MMLU Pro test, a key part of the Grok 4.1 Fast (Reasoning) vs Step 3.5 Flash debate, Grok 4.1 Fast (Reasoning) scores 90 against Step 3.5 Flash's 60. This data-driven approach is essential for any serious Grok 4.1 Fast (Reasoning) vs Step 3.5 Flash comparison.

This grouped bar chart provides a side-by-side comparison for each benchmark metric.

Speed & Latency

Speed is a crucial factor in the Grok 4.1 Fast (Reasoning) vs Step 3.5 Flash decision for interactive applications. The metrics below highlight the trade-offs you should weigh before shipping to production.

Time to First Token

Grok 4.1 Fast (Reasoning)300ms

Step 3.5 Flash300ms

Tokens per Second

Grok 4.1 Fast (Reasoning)108.559

Step 3.5 Flash203.967

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The Economics of Grok 4.1 Fast (Reasoning) vs Step 3.5 Flash

Power is only one part of the equation. This Grok 4.1 Fast (Reasoning) vs Step 3.5 Flash pricing analysis gives you a true sense of value.

Pricing Breakdown

Compare input and output pricing at a glance.

Real-World Cost Scenario

To process 1M input tokens and generate 250k output tokens, Grok 4.1 Fast (Reasoning) would cost $0.000, whereas Step 3.5 Flash would cost $0.000. This practical calculation is vital for any developer considering the Grok 4.1 Fast (Reasoning) vs Step 3.5 Flash choice.

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Which Model Wins the Grok 4.1 Fast (Reasoning) vs Step 3.5 Flash Battle for You?

Choose Grok 4.1 Fast (Reasoning) if...

Your top priority is raw performance and capability.

You are working in a technical or scientific field requiring the highest accuracy.

Cost is a secondary concern to power in your Grok 4.1 Fast (Reasoning) vs Step 3.5 Flash decision.

Choose Step 3.5 Flash if...

You need a highly responsive model for user-facing applications.

Your budget is a primary consideration in the Grok 4.1 Fast (Reasoning) vs Step 3.5 Flash choice.

You are developing at scale where operational costs are critical.

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Your Questions about the Grok 4.1 Fast (Reasoning) vs Step 3.5 Flash Comparison

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