Compare/Gemini 3 Flash Preview (Reasoning) vs Grok 4.5 (high)

Gemini 3 Flash Preview (Reasoning)vsGrok 4.5 (high)

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

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Gemini 3 Flash Preview (Reasoning)

Input
$0.5/M
Output
$3/M
Speed
208 tok/s
TTFT
5.86s
SpaceXAI

Grok 4.5 (high)

Input
$2/M
Output
$6/M
Speed
96 tok/s
TTFT
17.19s

Winner by Category

Cheaper
Gemini 3 Flash Preview (Reasoning)
Faster (tok/s)
Gemini 3 Flash Preview (Reasoning)
Lower Latency
Gemini 3 Flash Preview (Reasoning)
Benchmarks (6-5)
Gemini 3 Flash Preview (Reasoning)

Pricing Comparison

MetricGemini 3 Flash Preview (Reasoning)Grok 4.5 (high)
Input ($/M tokens)$0.5$2
Output ($/M tokens)$3$6
Cost for 1M input + 100K output tokens:
Gemini 3 Flash Preview (Reasoning)$0.80
Grok 4.5 (high)$2.60

Speed Comparison

Output Speed (tokens/s) — higher is better
Gemini 3 Flash Preview (Reasoning)
208 tok/s
Grok 4.5 (high)
96 tok/s
Time to First Token (seconds) — lower is better
Gemini 3 Flash Preview (Reasoning)
5.86s
Grok 4.5 (high)
17.19s

Benchmark Comparison

Data from Artificial Analysis API — 12 benchmarks

Intelligence Index
37.853.8
Coding Index
72.4
Math Index
97.0
GPQA Diamond
89.8%93.1%
MMLU-Pro
89.0%
LiveCodeBench
90.8%
AIME 2025
97.0%
MATH-500
Humanity's Last Exam
34.7%40.3%
SciCode
50.6%54.1%
IFBench
78.0%
TerminalBench
38.6%
Gemini 3 Flash Preview (Reasoning)6 wins
5 winsGrok 4.5 (high)

Frequently Asked Questions

Which is cheaper, Gemini 3 Flash Preview (Reasoning) or Grok 4.5 (high)?

Gemini 3 Flash Preview (Reasoning) is cheaper overall. Its blended price (3:1 input/output ratio) is $1.13/M tokens vs $3.00/M for Grok 4.5 (high).

Which model performs better on benchmarks?

Gemini 3 Flash Preview (Reasoning) wins 6 out of 12 benchmarks compared to 5 for Grok 4.5 (high). See the detailed benchmark chart above for per-category results.

Which is faster for real-time applications?

Gemini 3 Flash Preview (Reasoning) generates tokens faster at 208 tok/s vs 96 tok/s. Gemini 3 Flash Preview (Reasoning) also has lower time-to-first-token (5.86s vs 17.19s).

When should I use Gemini 3 Flash Preview (Reasoning) vs Grok 4.5 (high)?

Choose based on your priorities: Gemini 3 Flash Preview (Reasoning) for lower cost, Gemini 3 Flash Preview (Reasoning) for stronger benchmark performance, and Gemini 3 Flash Preview (Reasoning) for faster generation. For latency-sensitive apps, check the TTFT comparison above.