Model
GPT-6 Luna.
Power
£
API cost
by OpenAI · released 22 September 2026
In plain English
OpenAI's cheapest GPT-6 model, at about a hundredth of Astra's price, built for work at scale.
Good for
Sorting, pulling out information, routing and short summaries.
Things to be aware of
Cheap models still make mistakes. Decide what a person checks, and when work moves up to a stronger model.
What OpenAI says
“Luna is for “focused, high-volume tasks”.”
What everyone else says
TechCrunch described it as the clerical tier and noted that OpenAI cut prices sharply against the 5.6 generation. TechCrunch, 22 September 2026
- Context window
- 1.1M tokens
- Knows up to
- May 2026
- Run it yourself
- No, online only
- API price
- $0.10 in / $0.50 out
- per million tokens