GPT-5.6 Luna vs Gemini 3.6 Flash
API pricing, benchmark indices and specs — updated 19 October 2026.
openai · A · API-only
Input / 1M
$0.20
Output / 1M
$1.20
AA index
37.3
proprietary · 1.0M context
google · B · API-only
Input / 1M
$0.75
Output / 1M
$3.75
AA index
34
proprietary · 1M context
Specification comparison
Differences are highlighted; identical values are muted.
| Specification | GPT-5.6 Luna | Gemini 3.6 Flash |
|---|---|---|
| Deployment | API-only (closed weights) | API-only (closed weights) |
| Parameters | n/a — API-only | n/a — API-only |
| Architecture | n/a — API-only | n/a — API-only |
| Context length | 1,050,000 | 1,048,576 |
| Licence | Proprietary | Proprietary |
| Commercial use | Per API terms | Per API terms |
| Languages | n/a — API-only | n/a — API-only |
| Downloads 30d | n/a — API-only | n/a — API-only |
| Downloads all time | n/a — API-only | n/a — API-only |
| Quantizations on the Hub | n/a — API-only | n/a — API-only |
| Gated | n/a — API-only | n/a — API-only |
| First seen on the Hub | n/a — API-only | n/a — API-only |
| API input price / 1M tokens | $0.20 | $0.75 |
| API output price / 1M tokens | $1.20 | $3.75 |
| Est. cost per 1M input + 1M output tokens | $1.40 | $4.50 |
| Cached input / 1M tokens | $0.02 | $0.075 |
| AA Intelligence Index | 37.3 | 34 |
| AA Coding Index | 71.4 | 69.2 |
| AA Agentic Index | 42.1 | 29 |
| Max output tokens | 128,000 | 65,536 |
| API providers | 3 | 2 |
| Tool calling | Yes | Yes |
| Reasoning mode | Yes | Yes |
API cost
Estimated cost of 1M input + 1M output tokens via OpenRouter
GPT-5.6 Luna
$1.40
Gemini 3.6 Flash
$4.50
GPT-5.6 Luna is 3.2× cheaper at list price.