ChatGPT Free Users Get Unlimited Text Chats & GPT-5.6 Luna

OpenAI is removing text-based chat limits for all ChatGPT users, a change announced this week. This comes after ChatGPT surpassed one billion weekly users. The update introduces a new model called GPT-5.6 Luna for Free and Go tier users, replacing GPT-5.5. These users also gain a "Think" button for higher reasoning effort on complex questions. However, separate limits will remain for files, images, voice, and image generation. Paying Plus and Pro subscribers are receiving an upgraded GPT-5.6 Sol model, designed for faster tasks. They also get a thinking slider to adjust reasoning effort. Internal testing shows factual errors dropped significantly with the new models. The Luna model and Think button are rolling out to Free and Go users this week, with unlimited text chats following next week. The upgraded Sol model is already live for Plus and Pro users. This move is significant as OpenAI faces increasing competition from other AI chatbots.