OpenAI said on August 7 that it updated ChatGPT for Plus and Pro users with a revised GPT-5.6 Sol model and a slider for response depth.

It also made GPT-5.6 Luna the default for Free and Go users, with unlimited text chats and a Think button planned for next week.

OpenAI said GPT-5.6 Sol is for everyday chat and should give more focused answers with fewer factual mistakes. Internal tests showed responses with at least one factual error were about 68% less common with Sol and 62% less common with Luna than with GPT-5.5 Instant.

Artificial Analysis said GPT-5.6 models are reasoning models with configurable effort levels. It said Sol scored 59 on its intelligence index, one point behind Claude Fable 5, and reported a small increase in hallucination rate vs. GPT-5.5.

The update applies only to ChatGPT’s chat experience. OpenAI said the GPT-5.6 Sol versions in Work and Codex are unchanged. Limits remain on uploads, images, and other tools for free users.

OpenAI said it added safeguards for users under 18 as the US Federal Trade Commission sought information from seven chatbot companies on risks to children and teens.

🔗 Source: OpenAI

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