Directory · Model comparison
Gemini 3.5 Flash vs GPT-5.6 Luna
Side-by-side API economics and benchmarks. Per-1M input and output rates, context window, and verified metrics.
Tale of the tape
Head-to-head specs pulled from each model profile.
| Metric | Gemini 3.5 Flash | GPT-5.6 Luna |
|---|---|---|
| Input cost / 1M | $1.50 | $1.00 |
| Output cost / 1M | $9.00 | $6.00 |
| Context window | 1,048,576 tokens | 1,050,000 tokens |
| MMLU score | — | — |
Cost verdict
Enter monthly input and output volumes to see total cost savings.
Gemini 3.5 Flash
- Input: 1M × $1.50 = $1.50
- Output: 1M × $9.00 = $9.00
- Total
- $10.50
GPT-5.6 Luna
- Input: 1M × $1.00 = $1.00
- Output: 1M × $6.00 = $6.00
- Total
- $7.00
Total cost savings
$3.50
GPT-5.6 Luna saves $3.50 per month vs the other model at this volume.
Model routing savings
Uses this page's verified rates. Gemini 3.5 Flash is the premium route (higher combined per-1M cost); GPT-5.6 Luna handles routine traffic.
All premium
Gemini 3.5 Flash
$525.00
100% of input and output on the premium route
Routed stack
80% → GPT-5.6 Luna
20% → Gemini 3.5 Flash
$385.00
- Routine slice
- $280.00
- Premium slice
- $105.00
Monthly savings
$140.00
26.7% lower
Rates pulled from this page's model database entries (gemini-3-5-flash, gpt-5-6-luna) — same per-1M input/output figures as Tale of the tape. Production routing needs quality gates and monitoring.
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