SAN FRANCISCO, CALIFORNIA / RankWire.AI / – OpenAI is expanding access to ChatGPT by offering unlimited text conversations with GPT-5.6 Luna to Free and Go plan users. The company announced the change will take effect next week and will be subject to safeguards against misuse. During the current rollout, GPT-5.6 Luna will also become the default model for these accounts. Additionally, free users will see a new Think button that allows the system to spend more time on complex questions before providing a response.
This new access applies only to text chats and does not remove all usage restrictions across ChatGPT. OpenAI clarified that limits will stay in place for file uploads, image generation, and other tools requiring extra processing. The Think feature will be introduced alongside unlimited text messaging next week. It grants GPT-5.6 Luna additional reasoning time for tasks that need more analysis. The company continues to enforce separate controls for features beyond standard text conversations, including tools available under different usage caps.
OpenAI introduced GPT-5.6 as a family of models that includes Luna, Sol, and Terra. Luna is the faster, more affordable option within this lineup. The company stated ChatGPT now reaches approximately one billion weekly users for searches, research, planning, writing, and other activities. With the latest update, Luna will be the primary ChatGPT model for users on Free and Go plans. This rollout broadens access to the core chat service while maintaining limits on specific tools.
Enhanced reasoning model for paid subscriptions
Subscribers to ChatGPT Plus and Pro will also get an updated GPT-5.6 Sol for daily use. Sol supports quick responses and deeper reasoning within the paid plan. OpenAI said the update offers more targeted answers and avoids unnecessary detail when a simpler reply suffices. Paid users will also gain a reasoning slider across web, mobile, and desktop. This feature lets users determine how much processing ChatGPT applies to research, planning, coding, writing, and other tasks.
The company also shared that internal tests show lower factual error rates in its latest models. These tests included prompts related to finance, medicine, and law, which require detailed factual responses. OpenAI noted that answers with at least one mistake decreased by roughly 62% with GPT-5.6 Luna compared to GPT-5.5 Instant. For GPT-5.6 Sol, errors dropped by about 68%. The company added that Sol now handles dates, numbers, sources, rules, and assumptions more accurately when such details are important.
Unlimited text access still enforces safety boundaries
OpenAI emphasized that its latest ChatGPT models include extra protections for users believed to be under 18. The safeguards aim to prevent romantic roleplay, age-restricted challenges, and claims that could replace real-world relationships. They also include limits related to sexual content, eating disorders, dangerous activities, restricted items, and graphic violence. The company mentioned that new evaluations are in place for responses involving younger users. Unlimited text conversations will continue to operate within the same safeguards when expanded access reaches Free and Go accounts.
This update focuses on the main ChatGPT experience rather than every OpenAI product using GPT-5.6 models. OpenAI clarified that GPT-5.6 Sol versions used in ChatGPT Work and Codex are not changing with this release. Paid users can now access the updated Sol model and reasoning controls. Free and Go users will get Luna as their default model this week. Unlimited text chats and the Think button will be available next week, with separate limits remaining for images, uploads, and other tools.