Compare/Gemini 2.5 Flash Preview (Reasoning) vs gpt-oss-20B (low)

Gemini 2.5 Flash Preview (Reasoning)vsgpt-oss-20B (low)

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-oss-20B (low)

Input
$0.06/M
Output
$0.2/M
Speed
265 tok/s
TTFT
0.42s

Winner by Category

Cheaper
Gemini 2.5 Flash Preview (Reasoning)
Faster (tok/s)
gpt-oss-20B (low)
Lower Latency
Gemini 2.5 Flash Preview (Reasoning)
Benchmarks (6-6)
Tie

Pricing Comparison

MetricGemini 2.5 Flash Preview (Reasoning)gpt-oss-20B (low)
Input ($/M tokens)$0$0.06
Output ($/M tokens)$0$0.2
Cost for 1M input + 100K output tokens:
Gemini 2.5 Flash Preview (Reasoning)$0.00
gpt-oss-20B (low)$0.08

Speed Comparison

Output Speed (tokens/s) — higher is better
Gemini 2.5 Flash Preview (Reasoning)
gpt-oss-20B (low)
265 tok/s
Time to First Token (seconds) — lower is better
Gemini 2.5 Flash Preview (Reasoning)
gpt-oss-20B (low)
0.42s

Benchmark Comparison

Data from Artificial Analysis API — 12 benchmarks

Intelligence Index
24.320.8
Coding Index
14.4
Math Index
62.3
GPQA Diamond
69.8%61.1%
MMLU-Pro
80.0%71.8%
LiveCodeBench
50.5%65.2%
AIME 2025
62.3%
MATH-500
98.1%
Humanity's Last Exam
11.6%5.1%
SciCode
35.9%34.0%
IFBench
57.8%
TerminalBench
4.5%
Gemini 2.5 Flash Preview (Reasoning)6 wins
6 winsgpt-oss-20B (low)

Frequently Asked Questions

Which is cheaper, Gemini 2.5 Flash Preview (Reasoning) or gpt-oss-20B (low)?

Gemini 2.5 Flash Preview (Reasoning) is cheaper overall. Its blended price (3:1 input/output ratio) is $0.00/M tokens vs $0.10/M for gpt-oss-20B (low).

Which model performs better on benchmarks?

It's a tie — both models win 6 benchmarks each across 12 evaluated categories. See the detailed benchmark chart above for per-category results.

Which is faster for real-time applications?

gpt-oss-20B (low) generates tokens faster at 265 tok/s vs 0 tok/s. Gemini 2.5 Flash Preview (Reasoning) also has lower time-to-first-token (0.00s vs 0.42s).

When should I use Gemini 2.5 Flash Preview (Reasoning) vs gpt-oss-20B (low)?

Choose based on your priorities: Gemini 2.5 Flash Preview (Reasoning) for lower cost, both perform similarly on benchmarks, and gpt-oss-20B (low) for faster generation. For latency-sensitive apps, check the TTFT comparison above.