OpenAI launches GPT-6 Sol and Luna: near Fable 5 on DeepSWE at up to 96% lower cost
OpenAIDevs · x · 2026-09-23
OpenAI announced GPT-6 Sol and GPT-6 Luna, the newest members of the GPT-6 family, alongside API price cuts.
Key facts:
- Thanks to improved caching and inference, both models ship at half the previous generation's API prices
- On DeepSWE v1.1 (long-horizon coding agent tasks): GPT-6 Sol (max) nearly matches Claude Fable 5 (xhigh) at 80% lower cost per task; GPT-6 Luna (max) is comparable to Fable 5 (medium) at 96% lower cost per task
- OpenAI says the lower prices make automating complex work at scale practical
Related event: OpenAI Launches GPT-6 Sol and Luna with 50% API Price Cut(6 posts)→
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