OpenAI
LLM
Light
Closed weights
GPT-5.6 Luna
126 days since OpenAI announced it ·
GPT-5.6 Luna is a closed-weights LLM from OpenAI, announced 9 Jul 2026. It costs $0.20 per 1M input tokens and $1.20 per 1M output tokens. Its context window is 1.05M tokens.
- Input
- $0.20
- per 1M tokens
- Cache write
- $0.25
- per 1M tokens
- Cache read
- $0.02
- per 1M tokens
- Output
- $1.20
- per 1M tokens
- Context window
- 1.05M
- tokens
- Parameters
- —
- not disclosed
- Announcement
- openai.com/index/gpt-5-6
- Docs
- developers.openai.com/api/docs/models/gpt-5.6-luna
Our coverage
We haven’t written about GPT-5.6 Luna yet.
OpenAI · Light
closed weights- GPT-6 Luna +75d
- GPT-5.6 Luna +114d
- GPT-5.4 nano +222d
- GPT-5 nano
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All modelsFacts last updated , from OpenAI’s own pages.