Gemini 3.5 Flash vs GPT-5.6 Luna
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 GPT-5.6 Luna.
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...
GPT-5.6 Luna
GPT-5.6 Luna is a fast, cost-efficient model in OpenAI's GPT-5.6 series. It is suited for high-volume, latency-sensitive tasks such as chat, classification, and lightweight agentic workflows, providing capable reasoning for...
Technical Specifications
| Specification | Gemini 3.5 Flash | GPT-5.6 Luna |
|---|---|---|
| Provider | OpenAI | |
| Context Window | 1,048,576 tokens | 1,050,000 tokens |
| Agent Suitability | 88/100 | N/A |
| Time to First Token (TTFT) | 200 ms | N/A |
| Deployment Model | managed api | managed api |
| Production Stability | stable | beta |
| API Available | Yes | Yes |
| Released Date | 2026-05-19 | 2026-07-09 |
API Pricing Comparison
Input Price per Million Tokens
Gemini 3.5 Flash
$1.50
GPT-5.6 Luna
$1.00
Output Price per Million Tokens
Gemini 3.5 Flash
$9.00
GPT-5.6 Luna
$6.00
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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
GPT-5.6 Luna Quirks & Gotchas
No developer gotchas reported.