OpenAI GPT-5.6 Sol and GPT-5.6 Luna Updates

OpenAI has updated GPT-5.6 Sol for Plus and Pro users to enhance factual reliability and response focus, while expanding access to GPT-5.6 Luna for Free users. These updates introduce a new reasoning slider for paid tiers and unlimited text-based interactions for free users, aiming to make high-reasoning intelligence more widely available.

GPT-5.6 Sol: Enhanced Reliability and Focus

GPT-5.6 Sol is now optimized for everyday ChatGPT conversations, providing more direct answers and tighter formatting. The model is designed to adapt its level of detail based on the specific query, avoiding unnecessary formatting and providing corrections when simple agreement is not useful.

Factual Accuracy Improvements

GPT-5.6 Sol demonstrates a significant reduction in factual errors compared to previous versions. In internal evaluations focusing on financial, medical, and legal prompts, responses containing at least one factual error were 68% less common with GPT-5.6 Sol than with GPT-5.5 Instant. For comparison, GPT-5.6 Luna also showed a 62% reduction in factual errors over the same baseline.

Unified Reasoning Experience

OpenAI has integrated the "Instant" and "Thinking" experiences into a single consistent tone and behavior. Plus and Pro users can now use a slider to control the amount of "thought" the model applies to a response. This allows users to toggle between quick answers for simple tasks and deeper reasoning for complex work such as coding, research, and multi-step planning.

Expanding Access for Free Users

GPT-5.6 Luna is becoming the default model for Free and Go users. This expansion includes two primary updates to the user experience:

  • Unlimited Text Chats: Free users will have unlimited text-based conversations without rate limits.
  • Think Button: A new "Think" button allows Free users to trigger higher reasoning capabilities for difficult questions, giving GPT-5.6 Luna more time to process the answer.

Availability and Constraints

The updated GPT-5.6 Sol is available to Plus and Pro users immediately. GPT-5.6 Luna will become the default for Free and Go users this week, with unlimited text chats and the Think button becoming available the following week (subject to abuse guardrails).

It is important to note that GPT-5.6 Sol updates are limited to the ChatGPT Chat experience; the versions powering Work and Codex remain unchanged. Limits continue to apply to file uploads, images, and other tools for Free users.

Safety and Protections for Minors

OpenAI has implemented specific safety training and evaluations for users under 18. The model is trained to avoid:

  • Romantic roleplay and presenting itself as a substitute for real-world relationships.
  • Age-restricted challenges and age-restricted goods.
  • Sexual content, eating disorders, body-image risks, and graphic violence.
  • Dangerous activities.

For users in this demographic, the model is designed to encourage connection with trusted adults when support is needed.

Sources

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