Gemini 2.5 Flash (Reasoning) vs Gemini 2.5 Flash Preview (Sep '25) (Reasoning)

Comparing 2 AI models · 6 benchmarks · Google

Most Affordable
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Gemini 2.5 Flash (Reasoning)
$0.30/1M
Highest Intelligence
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Gemini 2.5 Flash Preview (Sep '25) (Reasoning)
79.3% GPQA
Best for Coding
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Gemini 2.5 Flash Preview (Sep '25) (Reasoning)
42.5 Coding Index
Price Difference
1.0x
input cost range

Composite Indices

Intelligence, Coding, Math

Standard Benchmarks

Academic and industry benchmarks

Benchmark Winners

6 tests
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Gemini 2.5 Flash (Reasoning)

1
  • MATH 500
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Gemini 2.5 Flash Preview (Sep '25) (Reasoning)

5
  • GPQA
  • MMLU Pro
  • HLE
  • LiveCodeBench
  • AIME 2025
Metric
Google logo Gemini 2.5 Flash (Reasoning)
Google
Google logo Gemini 2.5 Flash Preview (Sep '25) (Reasoning)
Google
Pricing
Per 1M tokens
Input Cost $0.30/1M $0.30/1M
Output Cost $2.50/1M $2.50/1M
Blended Cost 3:1 input/output ratio
$0.85/1M $0.85/1M
Specifications
Organization Model creator
Google Google
Release Date Launch date
May 20, 2025 Sep 25, 2025
Performance & Speed
Throughput Output speed
299.0 tok/s 155.2 tok/s
Time to First Token (TTFT) Initial response delay
8658ms 8247ms
Latency Time to first answer token
8658ms 8247ms
Composite Indices
Intelligence Index Overall reasoning capability
51.2 54.4
Coding Index Programming ability
40.5 42.5
Math Index Mathematical reasoning
73.3 78.3
Standard Benchmarks
GPQA Graduate-level reasoning
79.0% 79.3%
MMLU Pro Advanced knowledge
83.2% 84.2%
HLE Hard language evaluation
11.1% 12.7%
LiveCodeBench Real-world coding tasks
69.5% 71.3%
MATH 500 Mathematical problems
98.1%
AIME 2025 Advanced math competition
73.3% 78.3%
AIME (Original) Math olympiad problems
82.3%
SciCode Scientific code generation
39.4% 40.5%
LCR Code review capability
61.7% 64.3%
IFBench Instruction-following
50.3% 52.3%
TAU-bench v2 Tool use & agentic tasks