# OpenAI launches GPT-6 Sol and Luna

> OpenAI added mid-range and budget tiers to its GPT-6 lineup, with lower API prices and a same-day rollout across ChatGPT Work, Codex and the API.

- Publication: Go Big News
- By Nifal Adam, Go Big News Staff (Staff News)
- Category: AI
- Published: 2026-09-23T17:57:02.154+00:00
- Canonical: https://www.gobignews.com/ai/openai-launches-gpt-6-sol-and-luna

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On September 22, [OpenAI](https://openai.com) rolled out GPT-6 Sol and GPT-6 Luna in ChatGPT Work, Codex and the API. Sol costs $2 per million input tokens and $10 per million output tokens, while Luna costs $0.10 and $0.50, respectively.

The company said in a post on X that Sol and Luna “build on the advances behind GPT-6 Astra, bringing much of its strengths into faster and more affordable models to support work at scale.” Plus, Pro, Business, Enterprise and Edu users can access both models in ChatGPT Work and Codex; Free and Go users can access Luna through the desktop app.

Sol's pricing is 50% below GPT-5.6 Sol's $4 per million input-token and $20 per million output-token rates. Luna is down from $0.20 per million input tokens and $1.20 per million output tokens. OpenAI said it made caching and inference more efficient and was passing the savings to customers through lower API pricing; agents using Sol or Luna receive a 90% discount on cached input-token reads.

OpenAI says Sol “makes about half as many mistakes as its predecessor, reaching Astra-level reliability at much lower cost.”

The releases place Astra in the premium tier, Sol in the mid-range tier and Luna in the budget tier, according to press analysis. The company previously introduced Astra for law, as [Go Big News reported](https://www.gobignews.com/ai/openai-launches-astra-for-law) on September 18.

OpenAI develops generative AI models and offers products including ChatGPT, Codex and ChatGPT Work. On July 31, the company said those products had reached more than 1 billion active users and more than 2 million businesses.

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## Companies in this story

- Openai: https://www.gobignews.com/company/openai

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## X profiles in this story

- @openai: https://www.gobignews.com/profile/openai