Compare/Kimi K2.5 (Non-reasoning) vs Gemini 3 Flash Preview (Reasoning)

Kimi K2.5 (Non-reasoning)vsGemini 3 Flash Preview (Reasoning)

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

Kimi

Kimi K2.5 (Non-reasoning)

Input
$0.6/M
Output
$3/M
Speed
45 tok/s
TTFT
2.81s
Google

Gemini 3 Flash Preview (Reasoning)

Input
$0.5/M
Output
$3/M
Speed
189 tok/s
TTFT
6.57s

Winner by Category

Cheaper
Gemini 3 Flash Preview (Reasoning)
Faster (tok/s)
Gemini 3 Flash Preview (Reasoning)
Lower Latency
Kimi K2.5 (Non-reasoning)
Benchmarks (0-1)
Gemini 3 Flash Preview (Reasoning)

Pricing Comparison

MetricKimi K2.5 (Non-reasoning)Gemini 3 Flash Preview (Reasoning)
Input ($/M tokens)$0.6$0.5
Output ($/M tokens)$3$3
Cost for 1M input + 100K output tokens:
Kimi K2.5 (Non-reasoning)$0.90
Gemini 3 Flash Preview (Reasoning)$0.80

Speed Comparison

Output Speed (tokens/s) — higher is better
Kimi K2.5 (Non-reasoning)
45 tok/s
Gemini 3 Flash Preview (Reasoning)
189 tok/s
Time to First Token (seconds) — lower is better
Kimi K2.5 (Non-reasoning)
2.81s
Gemini 3 Flash Preview (Reasoning)
6.57s

Editorial Analysis

Verdict. Gemini 3 Flash Preview (Reasoning) takes the aggregate benchmark matchup 1–0 across 1 categories. Real workloads usually care about a handful of specific tasks — see the per-benchmark table above.

Pricing. Both models sit in the budget bracket for output-token pricing. At 1.0× the per-million-token cost, Gemini 3 Flash Preview (Reasoning) is meaningfully cheaper if your traffic is output-heavy (long completions, document generation, agent loops). Gemini 3 Flash Preview (Reasoning) makes more sense when output volume is low and absolute reasoning quality justifies the premium.

Strengths. Kimi K2.5 (Non-reasoning) is strongest on Intelligence Index (30.1). Gemini 3 Flash Preview (Reasoning) leads on Intelligence Index (38.7).

Speed. On throughput, Gemini 3 Flash Preview (Reasoning) generates tokens at 189 tok/s versus 45 tok/s — about 76% faster. On time-to-first-token, Kimi K2.5 (Non-reasoning) responds in 2810ms vs 6570ms, which matters most for chat-style UIs.

Provider. Kimi and Google sell to overlapping but distinct developer audiences: Kimi tends to ship frontier reasoning models with premium positioning, while Google often prices more aggressively. Your existing vendor relationships, billing, and SLA preferences may matter as much as the raw numbers above.

Workload cost. Workload scenarios (per million requests at 30M input + 15M output tokens): Kimi K2.5 (Non-reasoning) costs $63.00 ($756/year); Gemini 3 Flash Preview (Reasoning) costs $60.00 ($720/year). At a smaller 5M-input/2M-output scale (single-developer tool or prototype): Kimi K2.5 (Non-reasoning) ≈ $9.00/run, Gemini 3 Flash Preview (Reasoning) ≈ $8.50/run. At agent/realtime scale (200M input / 100M output per million requests): Kimi K2.5 (Non-reasoning) ≈ $420/run, Gemini 3 Flash Preview (Reasoning) ≈ $400/run. Gemini 3 Flash Preview (Reasoning) becomes more attractive at higher volume — the absolute per-token pricing difference compounds when you ship at scale.

Recommendation. Both models have legitimate use cases — the right answer depends on whether you are optimizing for benchmark ceiling, latency, or unit cost. Start with the cheaper / faster model, evaluate against your specific task, and only switch if the upgrade shows a meaningful lift.

Head-to-head deltas

  • On throughput, Gemini 3 Flash Preview (Reasoning) is 4.24× faster (189 tok/s vs 45 tok/s). For streaming chat or real-time agents this alone often flips the recommendation.

Benchmark Comparison

Data from Artificial Analysis API — 12 benchmarks

Intelligence Index
30.138.7
Coding Index
Math Index
GPQA Diamond
MMLU-Pro
LiveCodeBench
AIME 2025
MATH-500
Humanity's Last Exam
SciCode
IFBench
TerminalBench
Kimi K2.5 (Non-reasoning)0 wins
1 winsGemini 3 Flash Preview (Reasoning)

Frequently Asked Questions

Which is cheaper, Kimi K2.5 (Non-reasoning) 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 $1.20/M for Kimi K2.5 (Non-reasoning).

Which model performs better on benchmarks?

Gemini 3 Flash Preview (Reasoning) wins 1 out of 12 benchmarks compared to 0 for Kimi K2.5 (Non-reasoning). 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 189 tok/s vs 45 tok/s. Kimi K2.5 (Non-reasoning) also has lower time-to-first-token (2.81s vs 6.57s).

When should I use Kimi K2.5 (Non-reasoning) 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.