OpenAI cuts GPT-5.6 Terra and Luna prices, uses Sol to optimize inference
OpenAI announced price reductions for its GPT-5.6 models: Terra dropped 20% and Luna dropped 80%. The company also detailed how it used GPT-5.6 Sol, an AI model, to optimize load balancing and the forward pass of the inference process, including rewriting production kernels with Codex. Additionally, ChatGPT now offers improved GPT-5.6 Sol with better accuracy and consistency, and expands access to GPT-5.6 Luna for free users with unlimited everyday chats.
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Simon Willison
Advancing the price-performance frontier with GPT‑5.6 Huge price drop from OpenAI today: GPT-5.6 Terra got a 20% reduction, and GPT-5.6 Luna got a massive 80% drop. OpenAI credit 5.6 Sol with enabling this: in How GPT‑5.6 fuses frontier intelligence with frontier efficiency they describe using 5.6 Sol to optimize load balancing, and more impressively to optimize inference itself: We also used GPT‑5.6 Sol to optimize the model’s forward pass: the computation that transforms inputs into next-token predictions. Even when individual operations are fast, excess memory movement, synchronization, and inefficient data layouts can leave GPUs idle. To avoid this, GPT‑5.6 Sol found work that could be precomputed, avoided, or parallelized. With Codex, GPT‑5.6 Sol autonomously rewrote and optimized our production kernels, the core code that executes the mathematical operations that make up the model. This worked in part because we’ve trained GPT‑5.6 to be effective at writing and improving kernels
OpenAI Blog
ChatGPT introduces improved GPT-5.6 Sol with better accuracy and consistency, plus expanded access for free users and unlimited everyday chats with GPT-5.6 Luna.