OpenAI is making big update to ChatGPT’s free and Go plans. The company is removing automatic model switching and will soon let these users chat without text limits. GPT-5.6 Luna will also become the default model for both tiers.
Luna, the smallest of three GPT-5.6 models released in July, is set to replace GPT-5.5 Instant this week. Unlimited text chats will follow next week, along with a new Think button that lets users control how much reasoning the model uses before replying.
However, file uploads and image generation will still have limits for free and Go users.
Smarter solution for users
Paid subscribers on Plus and Pro plans are getting an upgraded GPT-5.6 Sol, OpenAI’s top model. The new version focuses on shorter, more direct answers with cleaner formatting. Simple questions get quick replies, while complex tasks like research or planning still receive detailed responses.
OpenAI says the update also cuts down on factual errors, especially around numbers, dates, and sources. In internal tests using financial, medical, and legal questions, factual mistakes were about 68 per cent less common than with the older GPT-5.5 Instant.
Think button for paid plans
Plus, and Pro users will get the Think feature as well, but with more flexibility. Instead of a simple on/off switch, it works as a slider between “instant” and “pro” reasoning levels. Users can keep it low for everyday chats or turn it up for harder tasks like coding, writing, or research.
However, the Sol upgrade will not apply to ChatGPT Work or Codex, since it is built specifically for regular chat use, not specialised tools.
The rollout starts with Luna this week, followed by unlimited chats and the Think button next week.
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