Grok 4.1 Fast (Reasoning) vs Step 3.5 Flash 2603: 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 2603 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 2603 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 2603 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: 153.444tokens/sec

Step 3.5 Flash 2603

Other

Reasoning: 6
Coding: 3
Multimodal: 3
Long Context: 5
Blended Price / 1M tokens: $0.015
P95 Latency: 1000ms
Tokens per second: 187.87tokens/sec

Overall Capabilities

The capability radar provides a holistic view of the Grok 4.1 Fast (Reasoning) vs Step 3.5 Flash 2603 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 2603 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 2603`.

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 2603 debate, Grok 4.1 Fast (Reasoning) scores 90 against Step 3.5 Flash 2603's 60. This data-driven approach is essential for any serious Grok 4.1 Fast (Reasoning) vs Step 3.5 Flash 2603 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 2603 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 Flash 2603300ms

Tokens per Second

Grok 4.1 Fast (Reasoning)153.444

Step 3.5 Flash 2603187.87

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The Economics of Grok 4.1 Fast (Reasoning) vs Step 3.5 Flash 2603

Power is only one part of the equation. This Grok 4.1 Fast (Reasoning) vs Step 3.5 Flash 2603 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 2603 would cost $0.018. This practical calculation is vital for any developer considering the Grok 4.1 Fast (Reasoning) vs Step 3.5 Flash 2603 choice.

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Which Model Wins the Grok 4.1 Fast (Reasoning) vs Step 3.5 Flash 2603 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.

You need the most advanced reasoning capabilities available.

Choose Step 3.5 Flash 2603 if...

You are developing at scale where operational costs are critical.

You prioritize cost-effectiveness over maximum performance.

Your workload requires consistent, reliable performance.

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Your Questions about the Grok 4.1 Fast (Reasoning) vs Step 3.5 Flash 2603 Comparison

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