Advancing the price-performance frontier with GPT-5.6

Yesterday, we shared how GPT‑5.6⁠ helped make itself more efficient to run⁠. Today, we’re passing those gains on to customers with lower prices for GPT‑5.6 Luna⁠(opens in a new window) and Terra⁠(opens in a new window) and faster performance with GPT‑5.6 Sol⁠ in the API. Together, these updates help customers get more from every dollar they invest in AI and move faster when time matters.

Starting today, GPT‑5.6 Luna, our fastest and most affordable model, will cost 80% less, while GPT‑5.6 Terra, our balanced model for everyday work, will cost 20% less. These lower prices for Luna and Terra are also reflected in how usage is counted against paid subscriptions when using Codex and ChatGPT Work. Luna gives businesses a far more cost-effective way to handle high-volume work at very high levels of quality. It can use tools and complete multi-step workflows, making a broader range of AI applications practical to run at scale.

Making advanced intelligence more abundant and affordable is central to OpenAI’s mission to ensure AGI benefits all of humanity. These changes put that commitment into practice. They reflect years of improvements in how our models are built, served, and put to work.

We’re also introducing Fast mode in the API, which replaces our Priority Processing offering. For GPT‑5.6 Sol, Fast mode now delivers up to 2.5× faster speeds than Standard processing at twice the price, with no change in intelligence. Fast mode is backward compatible: requests tagged priority will automatically use Fast mode.

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Matching intelligence to the outcome

Using AI efficiently begins with the outcome. The stakes, cost of error, urgency, and scale determine the right balance of intelligence, speed, reliability, and cost. That balance can change from one step of a workflow to the next.

The GPT‑5.6 family expands the range of those choices. Businesses can apply the maximum useful intelligence at every stage while paying the right price for the value it creates.