Which model is better: Gemini 2.5 Flash or OpenAI o3-mini?

**Gemini 2.5 Flash delivers superior overall value, beating OpenAI o3-mini across cost, latency, and coding benchmarks.** Gemini 2.5 Flash is 72.7% cheaper for inputs ($0.30 vs. $1.10/1M tokens) and lower on outputs ($2.50 vs. $4.40). It responds 1090ms faster with a 110ms TTFT and leads SWE-bench (58.0% vs. 49.3%).
Verified daily via automated API latency tests and official documentation.

Verified Performance & Unit Economics Delta

Daily synchronized metrics from synthetic latency endpoints and benchmark evaluations.

Metric / Dimension Gemini 2.5 Flash OpenAI o3-mini Net Delta / Advantage
Input Cost / 1M Tokens $0.30 $1.10 Gemini 2.5 Flash is 3.7x cheaper
Output Cost / 1M Tokens $2.50 $4.40 Gemini 2.5 Flash (43.2% lower)
Prompt Cache Read / 1M $0.030 $0.550 Gemini 2.5 Flash is 18.3x cheaper
Prompt Cache Write / 1M $0.30 $1.10 Gemini 2.5 Flash is 3.7x cheaper
Avg TTFT Response Latency 110ms 1250ms Gemini 2.5 Flash (+1140ms faster)
SWE-bench Verified (Coding) 58% 49.3% Gemini 2.5 Flash (+8.7% lead)
Inference Value Score (IVR) 66.8 / 100 58.2 / 100 Gemini 2.5 Flash (+8.6 pts)

Interactive Monthly Token Economics & ROI Forecaster

Model your expected production workload across prompt (input) and completion (output) tokens with prompt caching economics.

Live Calculation Engine
10.0M Tokens
100K 50M 250M 500M+
2.5M Tokens
100K 10M 50M 100M+

Estimated Monthly Spend

Gemini 2.5 Flash $9.25

$0.30/1M in · $2.50/1M out

Prompt Cache: $0.030/1M read · $0.30/1M write

OpenAI o3-mini $22.00

$1.10/1M in · $4.40/1M out

Prompt Cache: $0.550/1M read · $1.10/1M write

Projected Monthly Cost Reduction
$12.75 / mo
(58.0% lower cost with Gemini 2.5 Flash)
A

When to Choose Gemini 2.5 Flash

Choose Gemini 2.5 Flash when you need Hybrid reasoning model delivering unmatched price-performance across 1M context with configurable thinking budgets. and have an infrastructure budget aligned with $0.30/1M tokens.

B

When to Choose OpenAI o3-mini

Choose OpenAI o3-mini when you need High-throughput STEM reasoning, competitive coding, and low-latency algorithmic problem solving with configurable thinking effort. and prioritize OpenAI ecosystem integration at $1.10/1M tokens.

Related Questions & Decision Factors

Which is cheaper: Gemini 2.5 Flash or OpenAI o3-mini?

Gemini 2.5 Flash is cheaper at $0.30/1M input tokens compared to $1.10/1M for OpenAI o3-mini.

Which model has lower latency: Gemini 2.5 Flash or OpenAI o3-mini?

Gemini 2.5 Flash delivers faster response times with an average TTFT of 110ms vs 1250ms for OpenAI o3-mini.

When should you choose Gemini 2.5 Flash?

Choose Gemini 2.5 Flash when you need Hybrid reasoning model delivering unmatched price-performance across 1M context with configurable thinking budgets. and have an infrastructure budget aligned with $0.30/1M tokens.

When should you choose OpenAI o3-mini?

Choose OpenAI o3-mini when you need High-throughput STEM reasoning, competitive coding, and low-latency algorithmic problem solving with configurable thinking effort. and prioritize OpenAI ecosystem integration at $1.10/1M tokens.

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