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Latest from X - 2026-06-26

2 min read

Key Points

  • OpenAI: OpenAI announced a limited preview of the GPT‑5.6 family—Sol, Terra and Luna.
  • Sol is the new flagship, described as a step‑function improvement over GPT‑5.5.
  • Terra delivers performance competitive with GPT‑5.5 at roughly 2× lower cost, and Luna is the most cost‑efficient model, offering strong capability at the lowest price.
  • The company plans to make the three models generally available in the coming weeks, but the preview is currently limited to a small group of trusted partners in Codex and the API at the request of the U.S.
  • government.

Account Highlights

Updates by Account

OpenAI (@OpenAI)

Introducing a limited preview of GPT-5.6 Sol, our next generation frontier model, as well as GPT-5.6 Terra, a balanced model for efficient, everyday work, and GPT-5.6 Luna, a fast and affordable model for high-volume work.

https://t.co/OoM83SyISN

Sol is our new flagship and a step function better than GPT-5.5.

Terra delivers performance competitive to GPT-5.5 at 2x lower cost.

Luna is our most cost-efficient model, delivering strong capability at our lowest cost.

Together, the GPT-5.6 family gives people and developers https://t.co/Wm7wF3abHN

We believe in broad access and plan to make GPT-5.6 Sol, Terra, and Luna generally available in the coming weeks.

For now, at the request of the U.S. government, we’re starting with a limited preview among a small group of trusted partners in Codex and the API.

Sources

  1. https://x.com/OpenAI/status/2070555272230384038
  2. https://x.com/OpenAI/status/2070555274835046430
  3. https://x.com/OpenAI/status/2070555273467687257