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

Grok 4.5 (high)vsGemini 3 Flash Preview (Reasoning)

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

SpaceXAI

Grok 4.5 (high)

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

Gemini 3 Flash Preview (Reasoning)

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

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 (5-6)
Gemini 3 Flash Preview (Reasoning)

Pricing Comparison

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

Speed Comparison

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

Benchmark Comparison

Data from Artificial Analysis API — 12 benchmarks

Intelligence Index
53.837.8
Coding Index
72.4
Math Index
97.0
GPQA Diamond
93.1%89.8%
MMLU-Pro
89.0%
LiveCodeBench
90.8%
AIME 2025
97.0%
MATH-500
Humanity's Last Exam
40.3%34.7%
SciCode
54.1%50.6%
IFBench
78.0%
TerminalBench
38.6%
Grok 4.5 (high)5 wins
6 winsGemini 3 Flash Preview (Reasoning)

Frequently Asked Questions

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

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. However, Gemini 3 Flash Preview (Reasoning) has lower time-to-first-token (5.86s vs 17.19s).

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

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.