GPT 6 Explained: Models, Release Dates, Access, and Prices

GPT 6's general-purpose models have standard API prices ranging from $0.10 to $10 per million input tokens. Use GPT-6.1 Sol as the starting point for complex paid work, GPT-6.1 Terra for defined visual and app tasks, GPT-6 Luna for inexpensive repeatable tasks, and GPT-6 Astra when the hardest problems justify the premium. In ChatGPT, your plan and the experience you open determine which family member you get.

Verified against OpenAI's announcements, product documentation and API pricing on October 31, 2026. Recommendations and worked budgets below are editorial analysis, not results from a hands-on model test.

What Is GPT 6?

GPT-6 names a model family; ChatGPT, Work, Codex and the API are ways to use it. A model is the system generating the answer. The product around it supplies the interface, tools, permissions and billing.

The family includes GPT-6 Astra, the premium choice for demanding work; GPT-6 Sol, the original middle option; GPT-6.1 Sol, its newer upgrade; GPT-6.1 Terra, the fast, efficient option for visual and everyday professional work; and GPT-6 Luna, the inexpensive option for focused work at scale. OpenAI's Astra announcement, Sol and Luna announcement and GPT-6.1 Sol announcement establish the Astra, Sol and Luna roles.

Since October 26, 2026, GPT-6.1 Terra has offered an option for professional work combining image understanding, computer use and clear writing. Computer use means acting through software interfaces, not just describing a screen. Its standard token prices sit between Luna and 6.1 Sol. See OpenAI's Terra announcement and our GPT-6.1 Terra guide for the detailed switching decision.

For a buyer, “includes GPT-6” is an incomplete specification. Ask which model, in which experience, with which allowance. A Chat conversation using Sol and a Codex task using Astra can sit under the same subscription while providing different capabilities and consuming different allowances.

GPT-6 Pricing: What Each API Model Costs

Luna has the lowest token prices; Terra sits below both Sol models, which share ordinary input and output rates. All prices below are US dollars per million tokens, using Standard processing and short context. A token is a small unit of text processed by the model; input is what you send, output is what it generates, and cached input is eligible context reused from earlier processing.

Sources: OpenAI's public API pricing and detailed API rates for Astra, 6.1 Sol, Terra and Luna; the current GPT-6 Sol model page for original Sol.

These are usage rates, not subscription fees or prices per answer. OpenAI's public pricing page scopes its headline rates to context below 272,000 tokens. Longer context, speed modes, cache writes and tools can change the bill. For example, Standard short-context cache writes with 30-minute retention cost $2.50 per million tokens for GPT-6.1 Sol; the $0.10 cached-input rate describes reuse, not creating that cache. Detailed API rates.

For full application budgets and processing options, use our OpenAI API pricing guide.

GPT-6 Release Date: The Family Arrived in Stages

There is no single release date that describes every GPT-6 model and every product. The relevant sequence is:

• September 3, 2026: GPT-6 Astra was announced with an initial limited rollout. OpenAI said broader availability would follow, so the announcement date is not proof that every account had access that day. ChatGPT release notes.
• September 22, 2026: GPT-6 Sol and GPT-6 Luna arrived for Work, Codex and the API. OpenAI's launch.
• September 29, 2026: GPT-6.1 Sol was introduced as the Sol upgrade. OpenAI's dated Sol announcement update.
• October 7, 2026: GPT-6 with Intelligent UI began rolling out in paid ChatGPT Chat. October 8, 2026 was the announced expansion to Free and Go. OpenAI's dated Chat announcement.
• October 26, 2026: GPT-6.1 Terra arrived in Work, Codex and the API. OpenAI's model release notes.

The October Chat distinction matters if you heard “GPT-6 launched on October 8.” It describes the next stage of Chat access, after the underlying family had already reached other products.

Which GPT-6 Model Do You Get in ChatGPT?

Chat access follows your plan, and the October rollout does not turn regular Chat into GPT-6.1 Sol or Terra. OpenAI's rollout announcement maps the plans this way:

• Free and Go: GPT-6 Luna, starting with the October 8 expansion.
• Plus, Pro, Business and Enterprise: GPT-6 Sol in Chat, with the rollout starting October 7.
• Pro reasoning on eligible plans: GPT-6 Pro, powered by GPT-6 Astra, remains a separate choice.

The first two mappings come from the Chat launch announcement; Astra's Pro-effort distinction is confirmed in the Chat model guidance.

Intelligent UI is the ability to answer with an appropriate mix of text, visuals and interactive controls. A buyer comparing options might get an interactive comparison; an operator exploring a calculation might get a tool inside the conversation. OpenAI also says answers can start appearing while the model continues thinking. The release changes the Chat experience; it does not change the models powering Work or Codex. OpenAI's announcement.

The thinking levels still depend on your plan. OpenAI lists Medium and High for Plus, while Pro, Business and Enterprise also include Extra High and Pro, subject to workspace access. Intelligent UI works from Instant through Extra High where available; Pro effort with Astra does not support it. Model and thinking-level guidance.

A subscription decision should follow the work you need to do, not the family label. Our ChatGPT pricing guide covers the plans; Is GPT-6 Luna Free? separates included access from paid usage.

Where GPT-6 Runs in Work, Codex, and the API

Work and Codex provide a different model choice from Chat. ChatGPT Work handles longer tasks and finished deliverables such as reports or spreadsheets. Codex focuses on software development. OpenAI documents those roles in ChatGPT Work and Codex.

GPT-6 Astra: OpenAI includes limited Astra usage in Work and Codex on Plus and Business Standard, and supports it on eligible Pro and managed plans. Plus access to Astra in those experiences does not grant the Pro reasoning option in regular Chat. Astra is also available through the API as gpt-6-astra. Astra usage and availability and Chat model eligibility.

GPT-6 Sol: The launch included Work and Codex for Plus, Pro, Business, Enterprise and Edu, plus API access as gpt-6-sol. The October Chat rollout adds the conversation-tuned Sol experience for its named paid plans. Sol launch and Chat rollout.

GPT-6.1 Sol: OpenAI lists Plus, Pro, Business, Enterprise and Edu access in Work and Codex, and API access as gpt-6.1-sol. It is not listed as available in regular Chat. For a builder choosing a Sol model directly, this is the newer candidate to evaluate first. GPT-6.1 Sol availability.

GPT-6.1 Terra: OpenAI lists Plus, Pro, Business, Enterprise and Edu access in ChatGPT Work and Codex, with API access as gpt-6.1-terra. It is not available in regular Chat. Enterprise access depends on workspace and administrator settings; Terra does not support UAE inference residency. Terra product availability and API model page.

GPT-6 Luna: OpenAI launched Luna in Work and Codex for those paid plans and made it accessible to Free and Go users in the desktop app. The API identifier is gpt-6-luna; Free and Go Chat access was added in the October rollout. Luna launch availability.

Codex access itself is broader than Codex Cloud access: OpenAI includes Codex across ChatGPT plans, but excludes Free and Go from Codex Cloud. A desktop entitlement does not imply every cloud feature. Codex plan documentation.

The billing distinction is just as important. Signing into Codex with ChatGPT uses your plan's allowance; using your own API key uses API pricing. Do not estimate included subscription tasks by dividing your monthly fee by the API token table. OpenAI's billing explanation.

Which GPT-6 Model Should You Use?

Choose the least expensive option that passes your acceptance criteria, then escalate the tasks it cannot handle reliably. The following are editorial starting points based on OpenAI's model positioning and prices, not measured win rates from our own tests.

OpenAI presents Astra as its strongest option for difficult work, 6.1 Sol for complex projects, Terra for defined visual, writing and computer-use tasks, and Luna for focused high-volume work. Those roles support a starting point, not a promise about your workload. OpenAI's model-selection guidance.

For a funded founder, the acceptance criterion might be a feature that passes the existing checks. For an operations lead, it might be a correctly prepared report with traceable inputs. For a CTO, it might include permission boundaries and recovery from a failed tool call. “The answer sounds good” is too weak for all of them.

Our GPT-6 Sol vs Luna comparison goes deeper on the low-cost choice. The GPT-6.1 Sol vs GPT-6 Sol guide covers the upgrade decision.

What the Prices Mean for a Working Budget

The model choice can change token spend dramatically even before tools and retries enter the picture. Consider an illustrative monthly workload of 10,000 tasks, each using 2,000 uncached input tokens and 500 total billable output tokens. These are scenario assumptions, not measured usage. Assume Standard short-context processing and exclude tools, cache writes and regional surcharges.

That is 20 million input tokens plus 5 million output tokens. Applying the verified rates gives:

• GPT-6 Luna: $4.50, calculated as 20 × $0.10 + 5 × $0.50.
• GPT-6.1 Terra: $45, calculated as 20 × $1 + 5 × $5.
• GPT-6 Sol or GPT-6.1 Sol: $90, calculated as 20 × $2 + 5 × $10.
• GPT-6 Astra: $450, calculated as 20 × $10 + 5 × $50.

These are our calculations from OpenAI's API prices, holding token counts constant. Models may use different amounts of reasoning, context and iteration to complete the same job.

The historical comparison also needs precision. OpenAI's Sol/Luna launch listed the previous promotional GPT-5.6 Sol rates at $4 input and $20 output, and GPT-5.6 Luna at $0.20 input and $1.20 output, per million tokens. At those rates, the same workload would cost $180 for Sol or $10 for Luna. The new totals save $90, or 50%, for Sol, and $5.50, or 55%, for Luna. The latter is our weighted calculation, not a blanket claim that every Luna billing component fell by the same percentage. OpenAI's launch comparison.

When Does Trying Luna First Stop Saving Money?

Under the example's assumptions, a Luna attempt costs $0.00045 and a Sol attempt $0.009. If a failed Luna attempt always triggers a fresh, equally sized 6.1 Sol attempt, the expected cost is:

$0.00045 + retry share × $0.009.

That equals going straight to Sol at a 95% retry share. At a hypothetical 10% retry share, token spend would be $13.50 for the workload, versus $90 using Sol directly. This is an accounting boundary, not an acceptable failure target: extra context, evaluation calls, latency and human review can erase the saving well before it.

For an operator, the more useful comparison is the $85.50 premium for starting every task on Sol. If Luna creates review work worth more than that, the cheaper token rate has not produced the cheaper process. Similarly, Astra costs $360 more than Sol in this scenario; it earns that premium only if better outcomes or less rework justify it.

The Sol Upgrade Cuts the Cached Portion

GPT-6.1 Sol halves original Sol's cached-input rate; it does not halve the whole bill. For an illustrative 100 million cache-hit tokens, original Sol costs $20 and 6.1 Sol costs $10, a $10 saving on that component. Fresh input, output and cache creation still need their own accounting. OpenAI's cached-price comparison.

What Is Overhyped About GPT-6?

A shared family name does not establish a shared experience or a shared cost per completed task. The most consequential misunderstanding is treating “GPT-6 in Chat” as proof that a user is running the same model configuration as a builder's API agent. OpenAI explicitly describes the Chat models as tuned for everyday conversation, with Work and Codex unchanged by that release. Chat announcement.

The price ratios are useful but narrower than they look. Astra's standard ordinary input and output rates are 5 times Sol's, while Sol's are 20 times Luna's. Those are price ratios, not intelligence scores. A failed cheap run followed by a long repair can cost more than a successful expensive run.

Intelligent UI also changes presentation, not your obligation to check a result. An interactive calculator can make assumptions easier to inspect; its attractive interface does not establish that the assumptions are correct. A procurement comparison still needs current terms. A generated feature still needs validation.

For buying decisions, use vendor evaluations as evidence about what to try. Your own acceptance criteria determine what to keep. This guide does not convert OpenAI's benchmark claims into an independent performance ranking.

What to Change After GPT-5.5 Retired

GPT-5.5 retired from ChatGPT, ChatGPT Work and Codex on October 14, 2026. The OpenAI API is unaffected. OpenAI's model release notes confirm the retirement; its Codex model notice explains replacements and explicitly excludes API-key-authenticated Codex sessions.

If you use ChatGPT sign-in for Codex, check saved model selections, workspace defaults, scheduled tasks and scripts for gpt-5.5. Replace it with a model available to the account that actually runs the task, then validate the task before relying on it again. A personal account's access does not establish a managed workspace's access.

Act now if a saved selection still depends on the retired model. Wait for a representative evaluation before moving a stable, unrelated API workflow simply because a newer model exists. You are unaffected by this retirement notice if the dependency is API access rather than the ChatGPT-authenticated products it names.

Frequently Asked Questions

Why don’t I see GPT-6?

OpenAI says availability depends on rollout and workspace permissions. Look for the GPT-6 label in the Chat model menu; the paid Chat option is not labeled Sol. OpenAI's model FAQ.

Is access to the API included in ChatGPT Plus, Business, Enterprise or Edu?

API usage is metered separately from ChatGPT product allowances. However, eligible Pro and Business subscribers can now claim API credits by linking an API organization they own. Those credits do not increase ChatGPT or signed-in Codex limits and do not cover Codex usage through API keys. Check eligibility before assuming a subscription provides an API budget. OpenAI's API-credit benefit and pricing FAQ.

Will I be charged for API usage in the Playground?

Yes. OpenAI treats Playground usage as regular API usage and bills the applicable model rates. OpenAI's pricing FAQ.

Your Next Move

A builder should choose a model explicitly; a buyer should choose the needed experience and allowance. For your next working session, take a task you already understand and define what a correct result must contain before running it.

For a solo technical builder, begin complex work with 6.1 Sol and compare difficult failures with Astra. Try Terra on a defined visual or app task, checking the saved result before moving that workflow. For an operations lead, try Luna on a narrow repeated task with an objective check before letting it handle exceptions. For a CTO or procurement owner, record the model, product, sign-in method and workspace permissions together so a purchase decision matches what staff can use.

Keep the model that meets the standard at an acceptable total cost. Revisit the choice when the work or published terms change.

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