SI Model · OpenAI
GPT-6 Luna
| Developer | OpenAI |
|---|---|
| Released | September 22, 2026 |
| Status | Current |
| Inputs | Text, Images |
| Context window | 1.1M tokens |
| API price (input) | $0.10 / 1M tokens |
| API price (output) | $0.50 / 1M tokens |
| Open weights | No |
| Access | OpenAI API |
Specs and list prices last verified October 7, 2026. Prices change often; check the provider before you buy.
Strengths
- Very low price
- Fast responses
- Same ~1.05M-token context as the rest of the GPT-6 family
Best for
- Classification, extraction and routing at scale
- Chat features in consumer apps
- Sub-agents inside larger agent systems
GPT-6 Luna is the budget tier of OpenAI’s GPT-6 lineup, released on September 22, 2026 alongside GPT-6 Sol. At $0.10 per million input tokens and $0.50 per million output tokens, it is one hundred times cheaper than GPT-6 Astra on input.
Where it fits
| Model | Price (in / out per 1M) | Use |
|---|---|---|
| GPT-6 Astra | $10 / $50 | Hardest tasks |
| GPT-6.1 Sol | $2 / $10 | Best value for quality |
| GPT-6 Luna | $0.10 / $0.50 | High volume, low latency |
Typical uses
Small, fast models do most of the routine work in SI products: tagging support tickets, extracting fields from documents, moderating content, powering autocomplete and acting as cheap “workers” inside larger agent systems coordinated by a stronger model.
Luna’s main rival is Google’s Gemini 3.8 Flash. See GPT-6 Luna vs Gemini 3.8 Flash.
Sources
- OpenAI API models — OpenAI
Written by
Luka Kušec · Editor
Editor of SI.info. Writes about Super Intelligence, technology policy and the people building frontier models.