OpenAI has announced it is removing limits on text-based chats for all users of ChatGPT. The company, which recently reported crossing one billion weekly users, stated that free and Go users will also receive a new "Think" button for complex questions.
The GPT-5.6 Luna model will become the default for Free and Go users, replacing GPT-5.5. OpenAI confirmed that separate limits will remain for files, images, voice, and image generation.
ChatGPT Plus and Pro users will gain access to an upgraded GPT-5.6 Sol model, designed for quick tasks such as web research, advice, and writing, which is expected to provide more compact answers. These users will also get a thinking slider to adjust the model's processing for queries.
An internal evaluation by OpenAI indicated that GPT-5.6 Luna had 62% fewer factual errors compared to GPT-5.5-Instant, while GPT-5.6 Sol showed 68% fewer factual errors.