GPT-6 Luna
OpenAI's efficient tier — $0.10/$0.50 with the full 1.05M context
Verdict
Launched September 22, 2026. The default now for classification, extraction, summarisation, routing, and simple chat: $0.10 input / $0.50 output per million tokens, with the same context window as the flagship. It undercuts GPT-4o mini on price while sitting two model generations ahead, which removes the last cost argument for staying on the 4o or GPT-5 mini tiers.
Other Text Generation & Reasoning
- GPT-6 AstraProduction
OpenAI's most capable model — 1.05M context, 128K output
- GPT-6.1 SolProduction
The OpenAI default — near-Astra quality at a fifth of the price
- GPT-5.6Superseded
Previous OpenAI family — Sol/Terra/Luna tiers, superseded by GPT-6
- GPT-5Superseded
OpenAI's 2025 flagship — two families back now
- GPT-5 miniSuperseded
OpenAI's 2025 cost-efficient model — superseded by GPT-6 Luna
- GPT-4oSuperseded
OpenAI 2024 multimodal model — legacy, with retirement dates on Azure