OpenAI announced that it is lifting limits on text-based chats for all ChatGPT users; the service recently surpassed one billion weekly users. The company said the new GPT-5.6 Luna model will be the default for Free and Go accounts, replacing GPT-5.5 for text conversations.
New controls: Think button and thinking slider
Free and Go users will receive a new "Think" button that allows them to select higher reasoning power when tackling more complex questions. OpenAI noted that separate limits will remain in place for files, images, voice, and image generation.
Changes are coming for ChatGPT Plus and Pro subscribers as well. These users get access to an upgraded GPT-5.6 Sol model, tuned for quick tasks such as answering questions, web research, advice, planning, writing, and decision-making. OpenAI emphasized that this GPT-5.6 Sol is a distinct version from the Sol used for Codex and Work, which will remain unchanged.
Plus and Pro users also gain a thinking slider to adjust how much "thought" the model applies to an answer, letting them balance speed and depth depending on the complexity and number of steps required to solve a query.
Accuracy improvements and rollout schedule
According to OpenAI's internal evaluation, factual errors were 62% less common with GPT-5.6 Luna compared to GPT-5.5-Instant, and 68% less common with GPT-5.6 Sol.
The updated GPT-5.6 Sol is available to ChatGPT Plus and Pro users today. Other changes for Free and Go users are rolling out this week, and next week users will gain access to unlimited text chats and the new Think button for harder questions.
Why this matters
Removing text-chat limits for free users broadens access to extended, unconstrained text interactions. Combined with reported reductions in factual errors and new controls over reasoning intensity, the updates may change how users rely on ChatGPT for research, planning, and complex problem-solving.
