Grok 3 mini Reasoning (high) vs Grok 4 Fast (Reasoning)

Comparing 2 AI models · 6 benchmarks · xAI

Most Affordable
xAI logo
Grok 4 Fast (Reasoning)
$0.20/1M
Highest Intelligence
xAI logo
Grok 4 Fast (Reasoning)
84.7% GPQA
Best for Coding
xAI logo
Grok 4 Fast (Reasoning)
48.4 Coding Index
Price Difference
1.5x
input cost range

Composite Indices

Intelligence, Coding, Math

Standard Benchmarks

Academic and industry benchmarks

Benchmark Winners

6 tests
xAI logo

Grok 3 mini Reasoning (high)

1
  • MATH 500
xAI logo

Grok 4 Fast (Reasoning)

5
  • GPQA
  • MMLU Pro
  • HLE
  • LiveCodeBench
  • AIME 2025
Metric
xAI logo Grok 3 mini Reasoning (high)
xAI
xAI logo Grok 4 Fast (Reasoning)
xAI
Pricing
Per 1M tokens
Input Cost $0.30/1M $0.20/1M
Output Cost $0.50/1M $0.50/1M
Blended Cost 3:1 input/output ratio
$0.35/1M $0.28/1M
Specifications
Organization Model creator
xAI xAI
Release Date Launch date
Feb 19, 2025 Sep 19, 2025
Performance & Speed
Throughput Output speed
175.9 tok/s 176.3 tok/s
Time to First Token (TTFT) Initial response delay
573ms 3818ms
Latency Time to first answer token
11943ms 3818ms
Composite Indices
Intelligence Index Overall reasoning capability
57.1 60.3
Coding Index Programming ability
42.2 48.4
Math Index Mathematical reasoning
84.7 89.7
Standard Benchmarks
GPQA Graduate-level reasoning
79.1% 84.7%
MMLU Pro Advanced knowledge
82.8% 85.0%
HLE Hard language evaluation
11.1% 17.0%
LiveCodeBench Real-world coding tasks
69.6% 83.2%
MATH 500 Mathematical problems
99.2%
AIME 2025 Advanced math competition
84.7% 89.7%
AIME (Original) Math olympiad problems
93.3%
SciCode Scientific code generation
40.6% 44.2%
LCR Code review capability
50.3% 64.7%
IFBench Instruction-following
45.9% 50.5%
TAU-bench v2 Tool use & agentic tasks
90.4% 65.8%
TerminalBench Hard CLI command generation
16.3% 17.7%

Key Takeaways

Grok 4 Fast (Reasoning) offers the best value at $0.20/1M, making it ideal for high-volume applications and cost-conscious projects.

Grok 4 Fast (Reasoning) leads in reasoning capabilities with a 84.7% GPQA score, excelling at complex analytical tasks and problem-solving.

Grok 4 Fast (Reasoning) achieves a 48.4 coding index, making it the top choice for software development and code generation tasks.

All models support context windows of ∞+ tokens, suitable for processing lengthy documents and maintaining extended conversations.

When to Choose Each Model

xAI logo

Grok 3 mini Reasoning (high)

  • General-purpose AI
  • Versatile applications
xAI logo

Grok 4 Fast (Reasoning)

  • Cost-sensitive applications
  • High-volume processing
  • Complex reasoning tasks
  • Research & analysis
  • Code generation
  • Software development

Cost Calculator

xAI logo Grok 3 mini Reasoning (high)
$0.00
per month
xAI logo Grok 4 Fast (Reasoning)
$0.00
per month

Costs are estimates based on API pricing. Actual costs may vary based on caching, batch processing, and volume discounts.

AI Model Comparison Guide

Compare large language models (LLMs) side-by-side with detailed benchmark scores, pricing, and performance metrics. Our interactive comparison tool helps you evaluate AI models from OpenAI, Anthropic, Google, Meta, DeepSeek, and other leading providers. Use our AI model leaderboard to discover more models to compare.

Understanding Composite Indices

  • Intelligence Index: Aggregated score combining MMLU-Pro, GPQA, and HLE benchmarks - measures overall reasoning and knowledge capabilities
  • Coding Index: Composite metric from LiveCodeBench, SciCode, and LiveCodeBench Review - evaluates programming proficiency across multiple languages
  • Math Index: Combined score from AIME, AIME 2025, and MATH-500 benchmarks - assesses mathematical reasoning from high school to competition level

Key Comparison Metrics

  • Benchmark Scores: Standardized tests measuring intelligence, coding, math, and specialized capabilities - higher percentages indicate better performance
  • Pricing Analysis: Compare input and output token costs across models - critical for budgeting API usage and scaling applications
  • Performance Metrics: Throughput (tokens/second) and latency measurements for real-time application planning
  • Context Windows: Maximum token capacity for processing documents and maintaining conversation history

How to Compare AI Models Effectively

Performance vs Cost

Balance benchmark scores against token pricing - flagship models offer 10-15% better performance but cost 5-10x more than smaller alternatives

Task-Specific Selection

Prioritize relevant indices: coding index for development tasks, math index for STEM applications, intelligence index for general reasoning

Real-World Testing

Use our free AI chat interface to test models with your specific prompts before committing to API integration

All benchmark scores, pricing data, and performance metrics are sourced from Artificial Analysis and updated daily. Compare models by intelligence, coding ability, math performance, speed, cost, or release date using our comprehensive AI model leaderboard.