If you open ChatGPT today, the model writing back may no longer be the one you used yesterday. OpenAI announced that GPT-6 is now powering the Chat tab in ChatGPT, split across two models depending on your plan: GPT-6 Sol for Plus, Pro, Business, and Enterprise subscribers, and GPT-6 Luna for Free and Go users, which starts rolling out tomorrow.
The company says these GPT-6 models are tuned specifically for everyday conversation, rather than the heavier reasoning workloads the first GPT-6 models were introduced for last month (as 9to5Mac notes, OpenAI launched its first GPT-6 models in September). For OpenAI, the move matters because it puts its newest generation directly in front of hundreds of millions of casual users, not just paying power users.
OpenAI GPT-6 Sol and Luna: What Each Tier Gets
The split is simple, and it follows the plan you already pay for. According to OpenAI, GPT-6 Sol is live in the Chat tab for Plus, Pro, Business, and Enterprise accounts, while GPT-6 Luna will begin arriving for Free and Go users tomorrow. OpenAI has not announced separate pricing for either model, and both are delivered inside the existing ChatGPT tiers.
That means the practical difference for most people is which model answers by default, not a new subscription to buy. OpenAI has also not said whether Sol and Luna differ in speed, context window, or reasoning depth beyond their plan assignment, so treat any deeper claims about the two variants as unconfirmed for now.
- GPT-6 Sol: Plus, Pro, Business, Enterprise plans, available now in the Chat tab
- GPT-6 Luna: Free and Go plans, rolling out tomorrow
- Both ship inside existing ChatGPT subscriptions, no new tier announced



