GPT-6 Release Date, Models and ChatGPT Access

GPT-6 is not one model. It is OpenAI's newest model family, and it arrived in stages: GPT-6 Astra on September 3, 2026, then GPT-6 Sol and GPT-6 Luna, then GPT-6.1 Sol, and most recently GPT-6.1 Terra on October 26. This guide covers when each model came out, what OpenAI says each one is for, what the API costs, and which ChatGPT plans actually get GPT-6. Every fact below comes from OpenAI's own pages, checked on October 27, 2026.

Key Takeaways

• GPT-6 Astra launched on September 3, 2026, followed by GPT-6 Sol and GPT-6 Luna (September 22), GPT-6.1 Sol (September 29) and GPT-6.1 Terra (October 26) ^[1].
• Official API prices range from $0.10 to $10 per million input tokens and from $0.50 to $50 per million output tokens, from GPT-6 Luna at the bottom to GPT-6 Astra at the top ^[2].
• In ChatGPT, GPT-6 is rolling out to eligible Plus, Pro, Business and Enterprise users. Free and Go still default to GPT-5.6 Luna ^[3].
• GPT-6.1 Sol and GPT-6.1 Terra are not in ChatGPT's Chat view. They are offered in ChatGPT Work and Codex ^[3].
• On October 7, 2026, OpenAI started recommending the GPT-6 family for production API use ^[1].

GPT-6 at a Glance

What Is GPT-6?

GPT-6 is a family of models that share a generation but split the work by cost and speed. Picking "GPT-6" in practice means picking one of these models.

GPT-6 Astra: the top model

OpenAI calls GPT-6 Astra its "most capable model for the most demanding work" ^[2]. It is the most expensive model in the family and the one behind GPT-6 Pro in ChatGPT. OpenAI first opened it to a small group of organizations, then extended it to ChatGPT Plus, Pro, Business and Enterprise, the OpenAI API, Microsoft Azure and AWS Bedrock ^[4].

GPT-6 Sol and GPT-6.1 Sol: the workhorses

GPT-6 Sol arrived on September 22 as a reasoning model that takes text and image input ^[1]. In ChatGPT it powers most of the Chat reasoning levels. GPT-6.1 Sol followed a week later, and OpenAI describes it as "near-Astra performance for complex work at a lower cost" ^[2].

GPT-6 Luna and GPT-6.1 Terra: speed and volume

GPT-6 Luna is OpenAI's "most efficient model for focused, high-volume tasks", the kind of model you put behind classification, extraction or routing jobs. GPT-6.1 Terra, the newest member, is "a fast, efficient model for visual reasoning, precise computer use, and clear, natural writing" ^[2].

GPT-6 Release Date and Timeline

The short answer to "when was GPT-6 released" is September 3, 2026. The full family took about eight weeks to fill out.

Source: OpenAI API changelog.

Why the staggered rollout matters

If you read about GPT-6 in early September, you were reading about Astra alone. Prices, ChatGPT access and model names changed a lot over the next two months, so check the date on anything you read about "GPT-6" before relying on it.

Knowledge cutoffs

OpenAI lists different training cutoffs per model: April 30, 2026 for GPT-6 Astra and GPT-6.1 Sol, May 18, 2026 for GPT-6 Luna, and June 1, 2026 for GPT-6.1 Terra ^[2].

GPT-6 Models Compared

These are OpenAI's own positioning lines and standard API prices per million tokens. ChatGPT availability comes from OpenAI's help center.

GPT-6 Sol's price comes from the September 22 changelog entry and applies to prompts up to 272K input tokens ^[1]. The other prices come from OpenAI's models page ^[2]. Cached input, longer prompts and other processing tiers are priced separately by OpenAI.

Which GPT-6 model should you pick?

Start with GPT-6.1 Sol for complex coding and professional work, since OpenAI positions it close to Astra at a fifth of the price. Move to GPT-6 Astra only for the hardest tasks where quality matters more than cost. Use GPT-6 Luna for high-volume jobs, and try GPT-6.1 Terra when the task involves screenshots, computer use or polished writing.

Is GPT-6 in ChatGPT? Free, Plus and Pro

This is where most of the confusion around "ChatGPT 6" comes from. The answer depends on your plan and on which part of ChatGPT you use. The summary below follows OpenAI's help center article "GPT-6 and other models in ChatGPT", read on October 27, 2026 ^[3].

How Chat levels map to models

In the Chat view, the levels from Instant through Extra High run on GPT-6 Sol. The Pro level is GPT-6 Pro, which is powered by GPT-6 Astra and limited to Pro $100, Pro $200, Business and Enterprise.

Where GPT-6.1 Sol and Terra live

GPT-6.1 Sol and GPT-6.1 Terra do not appear in Chat. You reach them through ChatGPT Work and Codex. If you want to call them directly, the API is the straightforward route.

Is ChatGPT 6 free?

Not today. Free users do not get GPT-6 by default. Some third-party articles say otherwise, but OpenAI's help center lists GPT-5.6 Luna as the default for Free and Go.

How Developers Can Use GPT-6

All five GPT-6 models are available on the OpenAI API. GPT-6 Astra was also announced for Microsoft Azure and AWS Bedrock ^[4].

Migration notes from OpenAI

OpenAI's changelog lists a few changes for GPT-6 Astra: there is no none reasoning effort, custom temperature and top_p are not supported, and tool calling requires the Responses API ^[1]. Check these before you swap an older model name for a GPT-6 one.

Using GPT-6 through APIMart

If you already use several model providers, the GPT API on APIMart gives you the GPT-6 family behind one OpenAI-compatible key. The available model IDs are gpt-6-astra, gpt-6.1-sol, gpt-6.1-terra, gpt-6-sol and gpt-6-luna, and both Chat Completions and the Responses API are supported. The official OpenAI SDK works once you change the base URL:

from openai import OpenAI

client = OpenAI(api_key="YOUR_APIMART_KEY", base_url="https://api.apimart.ai/v1")

response = client.responses.create(
    model="gpt-6.1-sol",
    input="Summarize the GPT-6 model family in three bullet points.",
)
print(response.output_text)

APIMart's GPT API is billed per token; see the price table on the GPT API page for current rates.

GPT-6 vs GPT-5.6

GPT-5.6 is the previous generation, released on July 9, 2026, and it has not gone away. It is still the default for ChatGPT Free and Go users, where GPT-5.6 Luna handles everyday chats ^[3].

What changed for API users

On August 6, OpenAI recommended GPT-5.6 Sol for production. On October 7 it switched that recommendation to the GPT-6 family ^[1]. For new projects, that makes GPT-6 the default starting point.

Should you upgrade now?

Test before switching. Run your own prompts on GPT-6.1 Sol or GPT-6 Luna side by side with your current GPT-5.6 model, compare quality and token usage, and watch for the parameter changes listed above.

FAQs

When was GPT-6 released?

GPT-6 Astra, the first GPT-6 model, was released on September 3, 2026. GPT-6 Sol and GPT-6 Luna followed on September 22, GPT-6.1 Sol on September 29 and GPT-6.1 Terra on October 26, 2026.

Is GPT-6 free in ChatGPT?

No. According to OpenAI's help center, ChatGPT Free and Go users still default to GPT-5.6 Luna. GPT-6 is rolling out to eligible Plus, Pro, Business and Enterprise users.

What is the difference between GPT-6 Astra and GPT-6.1 Sol?

GPT-6 Astra is OpenAI's most capable model and costs $10 input and $50 output per million tokens. GPT-6.1 Sol offers what OpenAI calls near-Astra performance for complex work at $2 input and $10 output. For most professional work, GPT-6.1 Sol is the cheaper place to start.

What is GPT-6.1 Terra?

GPT-6.1 Terra is the newest GPT-6 model, released on October 26, 2026. OpenAI describes it as a fast, efficient model for visual reasoning, precise computer use and clear, natural writing. It costs $1 input and $5 output per million tokens on the OpenAI API.

How much does the GPT-6 API cost?

On the OpenAI API, standard prices run from $0.10 input and $0.50 output per million tokens for GPT-6 Luna up to $10 input and $50 output for GPT-6 Astra. Cached input and long prompts are priced separately on OpenAI's pricing page.

Can I use GPT-6 through an API?

Yes. All GPT-6 models are on the OpenAI API, and GPT-6 Astra was also announced for Microsoft Azure and AWS Bedrock. You can also call the whole family through APIMart's OpenAI-compatible endpoint with a single key.

What to Watch Next

OpenAI shipped five GPT-6 models in under two months, so expect ChatGPT access and model choices to keep changing. The two things most likely to move are Free and Go access, which still sits on GPT-5.6 Luna, and whether GPT-6.1 Sol and Terra come to the Chat view. We will update this page as OpenAI's help center and changelog change.