Gemini 3.5 Flash vs o3 Mini
How do these models stack up? Below is an expert side-by-side comparison of specifications, context window capacity, live pricing per million tokens, and standardized benchmark scores for Gemini 3.5 Flash and o3 Mini.
Gemini 3.5 Flash
Gemini 3.5 Flash is Google's high-efficiency multimodal model, bringing near-Pro level coding and reasoning at Flash-tier cost and speed. It is highly optimized for coding proficiency and parallel agentic execution...
o3 Mini
OpenAI o3-mini is a cost-efficient language model optimized for STEM reasoning tasks, particularly excelling in science, mathematics, and coding. This model supports the `reasoning_effort` parameter, which can be set to...
Technical Specifications
| Specification | Gemini 3.5 Flash | o3 Mini |
|---|---|---|
| Provider | OpenAI | |
| Context Window | 1,048,576 tokens | 200,000 tokens |
| Agent Suitability | 88/100 | 91/100 |
| Time to First Token (TTFT) | 200 ms | 800 ms |
| Deployment Model | managed api | managed api |
| Production Stability | stable | stable |
| API Available | Yes | Yes |
| Released Date | 2026-05-19 | 2025-01-31 |
API Pricing Comparison
Input Price per Million Tokens
Gemini 3.5 Flash
$1.50
o3 Mini
$1.10
Output Price per Million Tokens
Gemini 3.5 Flash
$9.00
o3 Mini
$4.40
Want to test both models live?
Run side-by-side prompt prompts in our dynamic Sandbox. Check execution speeds, latency metrics, and compute actual costs in real-time.
Benchmark Performance Metrics
Scores show the raw performance percentages verified across key evaluation suites. Higher bars indicate superior accuracy and capability in that domain.
Gemini 3.5 Flash Quirks & Gotchas
- ▸Excellent multimodal performance — native video understanding
- ▸Tool calling via Google's native function_declarations in Vertex AI
o3 Mini Quirks & Gotchas
- ▸Best cost/performance ratio for reasoning tasks in the OpenAI lineup
- ▸Still slower than GPT-5 for simple tool calls — route accordingly