OpenAI has rolled out a new family of models under the GPT-5.6 banner, introducing three distinct variants named Sol, Terra, and Luna, each aimed at a different slice of the market.
The full global release to ChatGPT, Codex, and the API went live on July 9, 2026, following a limited preview that kicked off on June 26, 2026, restricted to U.S. government-approved trusted partners.
Three models, three jobs
Sol is the flagship. It is built for heavy lifting: advanced coding, scientific research, and enhanced cybersecurity applications.
Terra sits in the middle. OpenAI positions it as delivering performance comparable to the previous GPT-5.5 generation, but at roughly half the cost.
Luna is designed for high-throughput, routine tasks where speed and cost efficiency matter more than raw capability.
The pricing math
Sol costs $5 per million input tokens and $30 per million output tokens. Terra comes in at $2.50 input and $15 output, exactly half of Sol across the board. Luna drops further to $1 input and $6 output, making it the most affordable option in the family by a significant margin.
The rollout also comes with enhanced safeguards, particularly around cybersecurity applications and misuse prevention.
About those names
Sol, Terra, and Luna happen to be identical, or nearly identical, to tickers and names associated with well-known blockchain projects: Solana trades as SOL, and the original Terra ecosystem gave the world LUNA before its spectacular collapse in 2022.
OpenAI has not announced any connection to blockchain technology, and nothing in the rollout suggests a link to digital assets. Some speculation has surfaced online, though without any substantive foundation in blockchain development or token announcements.