Which model is better: Gemini 2.5 Flash or OpenAI o3?
Gemini 2.5 Flash is 85.0% cheaper for input tokens ($0.30 vs. $2.00 per 1M tokens) and $2.50 vs. $8.00 for output tokens (6.7x cost advantage). In terms of operational performance, Gemini 2.5 Flash delivers lower response latency at 110ms TTFT (1040ms faster than OpenAI o3) with 180 vs. 82 tok/s throughput. OpenAI o3 leads coding evaluations at 71.7% SWE-bench Verified vs. 58.0% for Gemini 2.5 Flash and 87.7% vs. 70.5% on GPQA Diamond.
Verified daily via automated API latency tests and official documentation.
Zero-Shot RAG Verified
Verified Performance & Unit Economics Delta (12 Dimensions)
Daily synchronized metrics across token pricing, prompt cache economics, latency, throughput, and 5 capability benchmarks.
Metric / Dimension
Gemini 2.5 Flash
OpenAI o3
Net Delta / Advantage
Input Cost / 1M Tokens
$0.30
$2.00
Gemini 2.5 Flash is 6.7x cheaper
Output Cost / 1M Tokens
$2.50
$8.00
Gemini 2.5 Flash (68.8% lower)
Prompt Cache Read / 1M
$0.030
$0.500
Gemini 2.5 Flash is 16.7x cheaper
Prompt Cache Write / 1M
$0.30
$2.00
Gemini 2.5 Flash is 6.7x cheaper
Context Window (Max Output)
1,049k (66k out)
205k (100k out)
Gemini 2.5 Flash (5.1x larger context)
Avg TTFT Response Latency
110ms
1150ms
Gemini 2.5 Flash (1040ms faster)
Generation Speed (Throughput)
180 tok/s
82 tok/s
Gemini 2.5 Flash (+98 tok/s faster)
SWE-bench Verified (Coding)
58%
71.7%
OpenAI o3 (+13.7% lead)
GPQA Diamond (PhD STEM)
70.5%
87.7%
OpenAI o3 (+17.2% lead)
MMLU-Pro (Multi-Discipline)
82%
89.8%
OpenAI o3 (+7.8% lead)
MATH-500 (Quantitative Logic)
89%
98.6%
OpenAI o3 (+9.6% lead)
Inference Value Score (IVR)
66.6 / 100
60.6 / 100
Gemini 2.5 Flash (+6 pts)
Interactive Monthly Token Economics & ROI Forecaster
Model production workloads across prompt, completion, and cached context tokens, or switch models on the fly.
Gemini 2.5 Flash is cheaper at $0.30/1M input tokens ($2.50/1M output) compared to $2.00/1M input ($8.00/1M output) for OpenAI o3.
Which model has lower TTFT latency and higher tok/s throughput: Gemini 2.5 Flash or OpenAI o3?
Gemini 2.5 Flash delivers faster first-token latency at 110ms TTFT (180 tok/s throughput) compared to 1150ms TTFT (82 tok/s) for OpenAI o3.
How do Gemini 2.5 Flash and OpenAI o3 compare on SWE-bench coding and GPQA Diamond reasoning?
On SWE-bench Verified software engineering, Gemini 2.5 Flash scores 58% versus 71.7% for OpenAI o3. On GPQA Diamond graduate-level STEM reasoning, Gemini 2.5 Flash scores 70.5% versus 87.7% for OpenAI o3 (and 89% vs 98.6% on MATH-500).
When should you choose Gemini 2.5 Flash?
Choose Gemini 2.5 Flash (Google) for cost-efficient 1M-context summarization, multimodal extraction, and interactive assistants — offering a 1,048k context window, 110ms TTFT, and $0.30/1M input pricing ($0.030/1M cached reads).
When should you choose OpenAI o3?
Choose OpenAI o3 (OpenAI) for algorithmic synthesis, mathematical verification, PhD-level scientific research, and multi-step tool planning — offering a 204k context window, 1150ms TTFT, and $2.00/1M input pricing ($0.500/1M cached reads).
