Compare/Grok 4 Fast (Reasoning) vs Qwen2.5 Instruct 72B

Grok 4 Fast (Reasoning)vsQwen2.5 Instruct 72B

Side-by-side comparison of pricing, 12 benchmarks, and generation speed.

SpaceXAI

Grok 4 Fast (Reasoning)

Input
$0.2/M
Output
$0.5/M
Speed
TTFT
Alibaba

Qwen2.5 Instruct 72B

Input
$0.475/M
Output
$0.495/M
Speed
TTFT

Winner by Category

Cheaper
Grok 4 Fast (Reasoning)
Faster (tok/s)
Tie
Lower Latency
Tie
Benchmarks (10-1)
Grok 4 Fast (Reasoning)

Pricing Comparison

MetricGrok 4 Fast (Reasoning)Qwen2.5 Instruct 72B
Input ($/M tokens)$0.2$0.475
Output ($/M tokens)$0.5$0.495
Cost for 1M input + 100K output tokens:
Grok 4 Fast (Reasoning)$0.25
Qwen2.5 Instruct 72B$0.52

Speed Comparison

Speed data not available for these models.

Benchmark Comparison

Data from Artificial Analysis API — 12 benchmarks

Intelligence Index
27.49.6
Coding Index
Math Index
89.714.0
GPQA Diamond
84.7%49.1%
MMLU-Pro
85.0%72.0%
LiveCodeBench
83.2%27.6%
AIME 2025
89.7%14.0%
MATH-500
85.8%
Humanity's Last Exam
17.0%4.2%
SciCode
44.2%26.7%
IFBench
50.5%36.9%
TerminalBench
18.9%4.5%
Grok 4 Fast (Reasoning)10 wins
1 winsQwen2.5 Instruct 72B

Frequently Asked Questions

Which is cheaper, Grok 4 Fast (Reasoning) or Qwen2.5 Instruct 72B?

Grok 4 Fast (Reasoning) is cheaper overall. Its blended price (3:1 input/output ratio) is $0.28/M tokens vs $0.48/M for Qwen2.5 Instruct 72B.

Which model performs better on benchmarks?

Grok 4 Fast (Reasoning) wins 10 out of 12 benchmarks compared to 1 for Qwen2.5 Instruct 72B. See the detailed benchmark chart above for per-category results.

Which is faster for real-time applications?

Both models have comparable generation speeds.

When should I use Grok 4 Fast (Reasoning) vs Qwen2.5 Instruct 72B?

Choose based on your priorities: Grok 4 Fast (Reasoning) for lower cost, Grok 4 Fast (Reasoning) for stronger benchmark performance, and both have comparable speed. For latency-sensitive apps, check the TTFT comparison above.