GPT-5.6 Goes Public — Sol, Terra, and Luna Available Across ChatGPT and API

Summary: OpenAI lifted the restricted-partner cap on GPT-5.6 on July 9, making Sol, Terra, and Luna available to all ChatGPT users and API developers. The new Luna tier enters at the lowest price point in OpenAI's frontier lineup.

Key Facts

• Three tiers launched: Sol ($5/$30), Terra ($2.50/$15), Luna ($1/$6) per million input/output tokens
• Access expanded: Previously limited to ~20 government-vetted partners; now open to all ChatGPT and API users including Codex
• Luna is new territory: First OpenAI frontier model priced below GPT-4o mini — closing the gap with competitors
• Cerebras-accelerated Sol continues to run at up to 750 tokens/second for latency-sensitive agentic workloads

Why It Matters

Full public availability of GPT-5.6 resets the competitive landscape. With Grok 4.5 also launching this week, developers now have multiple Opus-class models under $10/M output tokens. Luna's pricing mirrors Grok 4.5's $6 output rate — suggesting a price floor is forming around $6/M for next-generation output tokens. Enterprise and developer benchmarking will intensify over the coming weeks as real workload comparisons become possible.

Read More

• AI News Today July 9, 2026 — BuildFastWithAI
• Last Week in AI: June 29–July 5 — Open Data Science