A cheap, fast pick for high-volume API work, and Free ChatGPT users can reach it in the desktop app.
Kenning's take
What it does
GPT-6 Luna is the efficient member of OpenAI's GPT-6 family, meant for focused tasks run at high volume. It is in the API and rolled out to ChatGPT Work and Codex, where Free and Go users can use it in the desktop app. OpenAI also uses it for its beta Decisions API.
- 1.05M-token context window
- Reasoning effort from none to max
- Text and image input
- Powers the Decisions API beta
Who it suits. Developers and ChatGPT users who want low cost and speed over top-end reasoning.
Key facts
- Category
- AI models
- Part of
- ChatGPT
- Made by
- OpenAI
- Based in
- United States
- Released
- 22 September 2026
- How to get it
- OpenAI API (model gpt-6-luna); ChatGPT Work and Codex on Plus, Pro, Business, Enterprise and Edu, and in the desktop app for Free and Go users
- Works on
- ChatGPT Work and Codex, API
- In the UK
- Yes
- Free plan
- Free and Go ChatGPT users can use Luna in the desktop app
- API price
- $0.10 per million input tokens, $0.50 per million output
FAQ
When was GPT-6 Luna released?
OpenAI released GPT-6 Luna on 22 September 2026.
Is GPT-6 Luna free?
Free and Go ChatGPT users can use it in the desktop app; the API costs $0.10 per million input tokens and $0.50 per million output.
Facts from the maker's own pages and the sources listed. Checked 2026-10-11.
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