OpenAI Introduces Unlimited Text Chats for Free Users, Improved GPT-5.6 Sol

OpenAI has introduced an improved version of GPT-5.6 Sol for everyday conversations while expanding access to its latest AI models for free ChatGPT users with unlimited text chats.

The company said the updated GPT-5.6 Sol delivers more focused answers, adjusts its level of detail based on the question and avoids unnecessary formatting.

“For a quick question, that means a direct answer with the context you need. For more involved work like multi-step planning, research or writing, it means a fuller response that keeps the main recommendation clear,” OpenAI said.

For ChatGPT Plus and ChatGPT Pro users, OpenAI said the same model now powers both Instant responses and deeper reasoning. Subscribers can also use a new slider in ChatGPT to control how much thought the AI model puts into an answer. The slider will be available on ChatGPT for the web, mobile and desktop.

“Move the slider up for planning, research, writing, coding, or decisions that need more thought,” the company said.

OpenAI also claimed that GPT-5.6 Sol is designed to make fewer mistakes, particularly on questions involving dates, numbers, sources, rules and assumptions.

“In an internal evaluation of financial, medical, and legal prompts requiring factual detail, responses containing at least one factual error were about 62% less common with GPT‑5.6 Luna and 68% less common with GPT‑5.6 Sol than with GPT‑5.5 Instant,” the company said.

The company also announced expanded access to its latest AI models for free users with unlimited text chats.

“We’re expanding access to our latest models for free users with unlimited text chats using GPT‑5.6 Luna, plus a new Think button for harder questions,” OpenAI said.

“For questions that require deeper reasoning, Free users can tap the new Think button to give GPT‑5.6 Luna more time to work through the answer,” it added.

The improved GPT-5.6 Sol model and the new reasoning slider are available to ChatGPT Plus and Pro users starting today. The updated model is currently limited to ChatGPT chat conversations.

OpenAI clarified that the version of GPT-5.6 Sol powering Work and Codex is not changing as part of this release.