OpenAI is making ChatGPT significantly more accessible to free users.

Starting this week, the company is rolling out a major update that brings GPT-5.6 Luna to Free and Go users as the default model while expanding access to unlimited text conversations. OpenAI is also introducing a new Think button that lets users ask Luna to spend more time reasoning through difficult questions.

Paid subscribers are not being left behind. GPT-5.6 Sol is also receiving an upgrade, with improvements aimed at making responses more focused and factually reliable. Plus and Pro subscribers are additionally getting a new reasoning slider that lets them control how much effort ChatGPT puts into generating an answer.

The changes mark one of the biggest updates to ChatGPT’s everyday experience since the GPT-5.6 family was introduced.

What’s New in ChatGPT?

OpenAI’s latest ChatGPT update can be broken down into four major changes:

• Free and Go users get GPT-5.6 Luna as the default model.
• Free and Go users are getting unlimited text conversations.
• A new Think button gives free users access to deeper reasoning when needed.
• Plus and Pro users get an updated GPT-5.6 Sol with a new reasoning slider.

OpenAI says the goal is to make more capable AI available to a larger number of people while improving the quality and consistency of responses.

Free ChatGPT Users Get Unlimited Text Conversations

Perhaps the most noticeable change for free users is the removal of the normal usage limit for text chats.

Previously, free ChatGPT users could eventually hit a usage limit after sending a certain number of messages. When that happened, they had to wait before continuing their conversation.

OpenAI is now expanding access so that Free and Go users can have unlimited text chats.

There is an important distinction, however.

Unlimited text conversations do not mean unlimited access to every ChatGPT feature. OpenAI says existing limits for capabilities such as image generation, file uploads, voice conversations, and image-related features still apply.

In other words, free users can chat more freely, but other resource-intensive features remain subject to usage limits.

GPT-5.6 Luna Is Now the Default Model for Free and Go

Alongside the expanded usage limits, OpenAI is making GPT-5.6 Luna the default model for Free and Go users.

Luna is designed as the faster and more efficient member of the GPT-5.6 family, making it particularly suitable for everyday conversations and general-purpose tasks.

OpenAI says Luna provides more reliable answers and fewer factual errors than the previous GPT-5.5 Instant experience.

The change means free users don’t need to manually select a new model to benefit from GPT-5.6 Luna. As the rollout reaches their accounts, Luna becomes part of the standard ChatGPT experience.

This is potentially a significant upgrade for people who use ChatGPT for everyday tasks such as:

• Writing and rewriting
• Research
• Summarizing information
• Homework and studying
• Brainstorming
• Coding assistance
• Planning
• General questions

What Is the New Think Button?

OpenAI is also adding a Think button for Free and Go users.

The idea is simple: most questions don’t require extensive reasoning, but some do.

For a quick question, users can simply ask ChatGPT normally. For a more complicated problem, they can select Think and give GPT-5.6 Luna additional reasoning time.

This can be useful for tasks involving:

• Multi-step problems
• Complex explanations
• Difficult reasoning
• Coding problems
• Detailed analysis
• Planning
• Questions requiring several pieces of information to be considered together

Importantly, OpenAI’s documentation says the Think feature available to Free and Go users uses GPT-5.6 Luna, rather than giving those users access to GPT-5.6 Sol.

That distinction is important because the free experience is not simply an unrestricted version of the higher-end Sol model.

GPT-5.6 Sol Gets an Upgrade for Plus and Pro Users

OpenAI is also updating GPT-5.6 Sol, its flagship model in the GPT-5.6 family.

The company says the updated model has been tuned to produce responses that are more focused and better adapted to the question being asked.

In practice, that means ChatGPT should be less likely to produce unnecessarily long answers when a concise response is sufficient, while still having the ability to provide deeper explanations when a task requires them.

OpenAI is also targeting factual reliability.

The company reports that the updated GPT-5.6 Sol produces fewer responses containing factual errors compared with GPT-5.5 Instant in its internal evaluations.

That should be particularly useful for tasks involving:

• Dates
• Numbers
• Rules
• Sources
• Assumptions
• Technical information
• Research
• Complex instructions

As always, improved accuracy does not mean an AI model is guaranteed to be correct. Important information should still be verified independently.

A New Reasoning Slider Gives Plus and Pro Users More Control

One of the more interesting additions for paid subscribers is a new reasoning slider.

Instead of having a fixed amount of reasoning applied to every request, eligible Plus and Pro users can choose how much effort ChatGPT should spend before producing an answer.

The basic idea is a trade-off between speed and reasoning depth.

If you’re asking something simple, you can use a lower reasoning setting and get an answer faster.

For a difficult programming problem, mathematical question, research task, or complicated analysis, you can increase the reasoning level and allow ChatGPT to spend more time working through the problem.

OpenAI’s documentation says GPT-5.6 Sol powers the Medium, High, and Extra High reasoning options on eligible paid plans, with availability depending on the subscription tier.

GPT-5.6 Luna vs. GPT-5.6 Sol

The two models serve different purposes within ChatGPT.

OpenAI describes Luna as the faster, more affordable model, while Sol is positioned as the flagship model for more demanding work.

When Will the New ChatGPT Features Be Available?

The rollout is happening progressively rather than all at once.

GPT-5.6 Sol and its new reasoning controls are rolling out to eligible paid users.

At the same time, GPT-5.6 Luna is being introduced as the default model for Free and Go users.

OpenAI says the new Think button for Free and Go users is scheduled to begin arriving the following week, while availability may vary as the rollout progresses.

If you don’t see the new model or controls immediately, that does not necessarily mean your account is excluded. OpenAI says GPT-5.6 is being gradually rolled out to eligible plans.

What Does This Mean for Free ChatGPT Users?

For free users, the update is arguably the biggest part of the announcement.

The combination of unlimited text chats + GPT-5.6 Luna + Think mode makes the free version of ChatGPT substantially more capable for everyday use.

Users who previously had to stop chatting because they reached a message limit can now continue their text conversations without the same restriction.

And when a question requires additional reasoning, the Think button provides an easy way to request a more deliberate answer.

This could make ChatGPT more useful for students, writers, developers, professionals, and casual users who don’t want to pay for a subscription.

What Does This Mean for ChatGPT Plus and Pro?

The biggest benefit for paid subscribers is not unlimited chatting. Instead, it is greater control over reasoning.

The new slider allows users to decide how much effort GPT-5.6 Sol should put into an answer.

That’s a useful change because not every question deserves the same amount of processing.

A simple request such as “Convert 10 miles to kilometers” doesn’t need extensive reasoning.

A request involving a large codebase, a complex business decision, advanced mathematics, or detailed research may benefit from significantly more reasoning.

The slider effectively gives users more control over that trade-off.

OpenAI Is Making ChatGPT More Adaptive

The broader direction behind these changes is clear: ChatGPT is becoming more adaptive.

Instead of forcing users into one fixed experience, OpenAI is giving different users different levels of access depending on their needs.

Free users get faster everyday intelligence through Luna, with the option to activate deeper reasoning through Think.

Paid users get Sol and more granular control over reasoning effort.

This approach also reflects the way AI assistants are increasingly being used. A single conversation can contain simple questions one moment and highly complex problems the next.

The ability to adjust reasoning effort accordingly can make the experience both faster and more efficient.

Conclusion

OpenAI’s latest ChatGPT update is more than a simple model refresh.

For Free and Go users, GPT-5.6 Luna becomes the default model, while unlimited text conversations remove one of the biggest restrictions of the free ChatGPT experience. The new Think button also provides a way to request deeper reasoning when a question is more complicated.

For Plus and Pro subscribers, the updated GPT-5.6 Sol focuses on more reliable and better-targeted responses, while the new reasoning slider provides greater control over how much effort ChatGPT uses.

The result is a ChatGPT experience that is increasingly designed around one simple idea: use less reasoning when speed matters and more reasoning when the problem demands it.

With GPT-5.6 Luna expanding access to more users and GPT-5.6 Sol becoming more controllable for paid subscribers, OpenAI is making another significant step toward turning ChatGPT into an AI assistant that can adapt its behavior to the complexity of the task.