Compare/Gemini 2.5 Flash Preview (Reasoning) vs GPT-5.4 mini (xhigh)

Gemini 2.5 Flash Preview (Reasoning)vsGPT-5.4 mini (xhigh)

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

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Gemini 2.5 Flash Preview (Reasoning)

Input
$0/M
Output
$0/M
Speed
TTFT
OpenAI

GPT-5.4 mini (xhigh)

Input
$0.75/M
Output
$4.5/M
Speed
219 tok/s
TTFT
3.82s

Winner by Category

Cheaper
Gemini 2.5 Flash Preview (Reasoning)
Faster (tok/s)
GPT-5.4 mini (xhigh)
Lower Latency
Gemini 2.5 Flash Preview (Reasoning)
Benchmarks (3-7)
GPT-5.4 mini (xhigh)

Pricing Comparison

MetricGemini 2.5 Flash Preview (Reasoning)GPT-5.4 mini (xhigh)
Input ($/M tokens)$0$0.75
Output ($/M tokens)$0$4.5
Cost for 1M input + 100K output tokens:
Gemini 2.5 Flash Preview (Reasoning)$0.00
GPT-5.4 mini (xhigh)$1.20

Speed Comparison

Output Speed (tokens/s) — higher is better
Gemini 2.5 Flash Preview (Reasoning)
GPT-5.4 mini (xhigh)
219 tok/s
Time to First Token (seconds) — lower is better
Gemini 2.5 Flash Preview (Reasoning)
GPT-5.4 mini (xhigh)
3.82s

Benchmark Comparison

Data from Artificial Analysis API — 12 benchmarks

Intelligence Index
24.348.1
Coding Index
51.5
Math Index
GPQA Diamond
69.8%87.5%
MMLU-Pro
80.0%
LiveCodeBench
50.5%
AIME 2025
MATH-500
98.1%
Humanity's Last Exam
11.6%26.6%
SciCode
35.9%49.9%
IFBench
73.3%
TerminalBench
52.3%
Gemini 2.5 Flash Preview (Reasoning)3 wins
7 winsGPT-5.4 mini (xhigh)

Frequently Asked Questions

Which is cheaper, Gemini 2.5 Flash Preview (Reasoning) or GPT-5.4 mini (xhigh)?

Gemini 2.5 Flash Preview (Reasoning) is cheaper overall. Its blended price (3:1 input/output ratio) is $0.00/M tokens vs $1.69/M for GPT-5.4 mini (xhigh).

Which model performs better on benchmarks?

GPT-5.4 mini (xhigh) wins 7 out of 12 benchmarks compared to 3 for Gemini 2.5 Flash Preview (Reasoning). See the detailed benchmark chart above for per-category results.

Which is faster for real-time applications?

GPT-5.4 mini (xhigh) generates tokens faster at 219 tok/s vs 0 tok/s. Gemini 2.5 Flash Preview (Reasoning) also has lower time-to-first-token (0.00s vs 3.82s).

When should I use Gemini 2.5 Flash Preview (Reasoning) vs GPT-5.4 mini (xhigh)?

Choose based on your priorities: Gemini 2.5 Flash Preview (Reasoning) for lower cost, GPT-5.4 mini (xhigh) for stronger benchmark performance, and GPT-5.4 mini (xhigh) for faster generation. For latency-sensitive apps, check the TTFT comparison above.