GPT-6 rolls out in ChatGPT: Sol for paid plans, Luna for Free and Go

OpenAI is bringing GPT-6 to everyone in ChatGPT, on free and paid plans, ‘globally’ in its own words. The rollout began on October 7, 2026 for Plus, Pro, Business and Enterprise. Free and Go users follow from the next day, October 8.

There are two versions. Paid plans get GPT-6 Sol; Free and Go get GPT-6 Luna. They replace GPT-5.6 Sol and GPT-5.6 Luna. Only Chat changes: Codex and ChatGPT Work keep their previous versions.

According to OpenAI, ChatGPT can now give a useful first answer while it keeps reasoning, then add detail as it goes. The company says GPT-6 Instant starts answering 44% sooner on average than GPT-5.6 Instant when search is needed, and that safety improved without adding unnecessary refusals. OpenAI says more than 1.2 billion people use ChatGPT each week.

In its system card, published October 7, OpenAI treats both models as ‘High’ capability in cybersecurity and in biological and chemical risks, but below ‘Critical’ in cybersecurity. Neither reaches ‘High’ in AI self-improvement. OpenAI also says GPT-6 resists jailbreaks better than GPT-5.6.

For developers: from October 8, an Ultrafast mode for GPT-6.1 Sol is rolling out in the API at $12 per million input tokens and $60 per million output tokens, with EU data residency supported. OpenAI says it is up to 8x faster than Sol Standard.