Compare/Grok 4 Fast (Non-reasoning) vs Phi-4

Grok 4 Fast (Non-reasoning)vsPhi-4

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

xAI

Grok 4 Fast (Non-reasoning)

Input
$0.2/M
Output
$0.5/M
Speed
123 tok/s
TTFT
0.30s
Microsoft Azure

Phi-4

Input
$0.125/M
Output
$0.5/M
Speed
37 tok/s
TTFT
0.41s

Winner by Category

Cheaper
Phi-4
Faster (tok/s)
Grok 4 Fast (Non-reasoning)
Lower Latency
Grok 4 Fast (Non-reasoning)
Benchmarks (11-1)
Grok 4 Fast (Non-reasoning)

Pricing Comparison

MetricGrok 4 Fast (Non-reasoning)Phi-4
Input ($/M tokens)$0.2$0.125
Output ($/M tokens)$0.5$0.5
Cost for 1M input + 100K output tokens:
Grok 4 Fast (Non-reasoning)$0.25
Phi-4$0.17

Speed Comparison

Output Speed (tokens/s) — higher is better
Grok 4 Fast (Non-reasoning)
123 tok/s
Phi-4
37 tok/s
Time to First Token (seconds) — lower is better
Grok 4 Fast (Non-reasoning)
0.30s
Phi-4
0.41s

Benchmark Comparison

Data from Artificial Analysis API — 12 benchmarks

Intelligence Index
23.110.4
Coding Index
19.011.2
Math Index
41.318.0
GPQA Diamond
60.6%57.5%
MMLU-Pro
73.0%71.4%
LiveCodeBench
40.1%23.1%
AIME 2025
41.3%18.0%
MATH-500
81.0%
Humanity's Last Exam
5.0%4.1%
SciCode
32.9%26.0%
IFBench
37.7%23.5%
TerminalBench
12.1%3.8%
Grok 4 Fast (Non-reasoning)11 wins
1 winsPhi-4

Frequently Asked Questions

Which is cheaper, Grok 4 Fast (Non-reasoning) or Phi-4?

Phi-4 is cheaper overall. Its blended price (3:1 input/output ratio) is $0.22/M tokens vs $0.28/M for Grok 4 Fast (Non-reasoning).

Which model performs better on benchmarks?

Grok 4 Fast (Non-reasoning) wins 11 out of 12 benchmarks compared to 1 for Phi-4. See the detailed benchmark chart above for per-category results.

Which is faster for real-time applications?

Grok 4 Fast (Non-reasoning) generates tokens faster at 123 tok/s vs 37 tok/s. Grok 4 Fast (Non-reasoning) also has lower time-to-first-token (0.30s vs 0.41s).

When should I use Grok 4 Fast (Non-reasoning) vs Phi-4?

Choose based on your priorities: Phi-4 for lower cost, Grok 4 Fast (Non-reasoning) for stronger benchmark performance, and Grok 4 Fast (Non-reasoning) for faster generation. For latency-sensitive apps, check the TTFT comparison above.