GPT-6 Sol release date: what OpenAI has actually confirmed
GPT-6 Sol is out. Its release date, $2/$10 API price, 1.05M context and ChatGPT plans, plus which of the leaks turned out right.
OpenAI released GPT-6 Sol on Tuesday 22 September 2026, together with a smaller sibling, GPT-6 Luna. It arrived a week before DevDay, the date most leakers had pencilled in, and on the Tuesday that one X account had predicted two days earlier.
Public status on 22 September 2026 at 21:30 UTC: GPT-6 Sol is released. It is in the OpenAI API as gpt-6-sol, at $2 per million input tokens and $10 per million output tokens, and in ChatGPT Work and Codex for Plus, Pro, Business, Enterprise and Edu users. OpenAI says it is not yet available in ordinary ChatGPT chats.
This page opened on 21 September as a leak tracker. Every claim from that version is still below, now scored against OpenAI's launch post, its model page and its API pricing page. Post times are the posts' own timestamps in UTC.
GPT-6 Sol at a glance
GPT-6 Sol | |
|---|---|
Released | Tuesday 22 September 2026 |
API id |
|
API price per million tokens | $2 input, $10 output, $0.20 cached input |
Context window | 1,050,000 tokens, with up to 128,000 output tokens |
Long prompts | Above 272,000 input tokens, the whole request is billed at 2x input and 1.5x output |
Reasoning effort | None, low, medium (the default), high, xhigh and max |
Knowledge cutoff | 20 April 2026 |
In ChatGPT | ChatGPT Work and Codex on Plus, Pro, Business, Enterprise and Edu. Not yet in Chat |
OpenAI frames the price as a 50% cut on GPT-5.6 Sol's promotional rate of $4 and $20. It also puts GPT-6 Sol below GPT-5.6 Terra, the tier underneath, which costs $2 and $12.
The tracker, scored after launch
Claim | Verdict | Who said it, and when | What OpenAI confirmed |
|---|---|---|---|
GPT-6 Sol exists and is in internal testing | Right | @pankajkumar_dev, 6 September, 09:35 | Released on 22 September |
It could launch at DevDay on 29 September | Wrong | The same post | It shipped a week before DevDay |
| Right id, never shown | @Mr_Salio, 13 September, 12:00, worded "reportedly" | The API id is |
Sol is below Astra's level | Right | @pankajkumar_dev, 6 September | OpenAI: "GPT-6 Astra continues to be our best model across the board" |
Sol matches or beats Astra | Mostly wrong | @Mr_Salio, 13 September | On one OpenAI chart, Sol at xhigh effort beats Astra at low effort. Overall, OpenAI ranks Astra first |
Sol runs about 6x faster than Astra | Overstated | @hqmank, 7 September | Artificial Analysis measured about 104 output tokens per second for Sol and 58 for Astra, under twice as fast |
OpenAI's main launch slipped into the week of 21 September | Right | Sam Altman, 16 September, 22:31 | Sol and Luna shipped on 22 September. Altman never named the launch he meant |
It lands on Tuesday 22 September | Right | @HarshithLucky3, 20 September, 13:47 | Released that day |
It will cost less than Astra | Right | Several accounts | $2 and $10, against Astra's $10 and $50 |
A whole GPT-6 family of Sol, Terra and Luna | Partly right | @pankajkumar_dev, 6 September | Sol and Luna shipped. There is no GPT-6 Terra yet |
MultiChats carries GPT-6 Sol | In progress | Our model registry, 22 September | We are adding GPT-6 Sol and GPT-6 Luna |
The leakers were right about the model, the tier and the day. Nobody leaked the price, the Luna launch, or the fact that ChatGPT would get Sol in Work and Codex before ordinary chats.
What OpenAI announced
OpenAI says it trained Sol and Luna "with similar methods as GPT-6 Astra", to bring Astra's advances to "faster, more affordable models". The launch post makes these claims, all measured by OpenAI:
Business workflows. On AutomationBench, Sol at xhigh effort scored 33.2%, ahead of Claude Opus 5 at max effort (26.9%) at 9% of Opus 5's cost per task.
Factual accuracy. On OpenAI's internal factuality evaluation, Sol "makes about half as many mistakes as its predecessor".
Coding. On DeepSWE v1.1, Sol at max effort scored 68.8%, within 1.1 points of Claude Fable 5's best result.
Writing style. OpenAI promises "more clarity, less jargon, fewer odd turns of phrase" and slightly shorter answers.
Caching. Cached input costs 10% of the normal rate, and changing the reasoning effort mid-conversation no longer throws away the cache.
The first independent numbers came in on launch day. Artificial Analysis gives GPT-6 Sol a score of 48 on its Intelligence Index at max effort, one point above GPT-5.6 Sol's 47 and five below GPT-6 Astra's 53. It also measured Sol using about 31,000 output tokens per task, close to GPT-5.6 Sol and about a quarter of what Claude Opus 5.5 used, so the low price is not eaten up by long answers.
First, separate the two models called Sol
OpenAI introduced its naming system with GPT-5.6 in June, and its preview post spells out the rule: "the number identifies a model's generation, while Sol, Terra, and Luna identify durable capability tiers that can advance on their own cadence."
So GPT-5.6 Sol and GPT-6 Sol are the same tier, one generation apart. GPT-5.6 Sol came out on 9 July and is still in the API as gpt-5.6-sol, with its promotional price running at least until 21 November. GPT-6 Sol is the new one, sitting below GPT-6 Astra. The whole ladder, with every price and plan, is in our explainer on OpenAI's model names.
How the rumour developed
6 September. Three days after Astra, @pankajkumar_dev posted "GPT-6 Sol Leaks": "OpenAI is now internally testing GPT-6 Sol. It is fast and quite good, though not at the level of Astra." The post floated DevDay as the launch and pitched Sol as "the middle ground between performance and limit especially for Plus users". Later that day the same account posted a DevDay wish list that included a whole "GPT-6 family: Sol, Terra and Luna".
6 September, again. @AGTPinsights relayed two tester reports: a BMW M4 drawn as an SVG "using about 28,000 tokens in roughly 3 minutes on max effort", and "a zero-shot render in 15 minutes using about 60,000 total tokens". Neither came with a prompt, a log or a tester's name.
7 September. @hqmank: Sol was "reportedly running at roughly 6x Astra's speed in a single test".
13 September. @Mr_Salio wrote that gpt-6-sol "reportedly appeared in the OpenAI API" and that Sol "will match Astra's raw intelligence". A Hacker News thread titled "GPT-6-sol appeared on OpenAI API" linked a Reddit post making the same claim. None of them showed a model list or an API response.
15 and 16 September. Sam Altman posted "big 🚢 this week", then wrote the next evening: "the main thing i was excited about launching this week will be next week instead, but imo worth the wait!"
20 September. In a post about an Anthropic leak, @HarshithLucky3 added that on Tuesday "we are getting something from OpenAI" as well.
22 September. OpenAI published "Introducing GPT-6 Sol and Luna", added both models to its API pricing page and began a gradual rollout in ChatGPT Work and Codex. Anthropic released Claude Opus 5.5 the same day.
GPT-6 Luna came with it
Luna is the smaller model from the same launch: gpt-6-luna in the API, at $0.10 per million input tokens and $0.50 per million output tokens, half GPT-5.6 Luna's price. OpenAI says that at higher effort levels it matches GPT-5.6 Sol on its factuality evaluation "at about a hundredth its cost". In ChatGPT, Free and Go users can use GPT-6 Luna in the desktop app.
Where MultiChats stands
We are adding GPT-6 Sol and GPT-6 Luna to MultiChats on our paid plans, alongside Claude Opus 5.5 from Anthropic's launch the same day. For the Anthropic side of the week, see our Claude Opus 5.5 page, and for the two new models side by side, Opus 5.5 vs GPT-6 Sol.
Frequently asked questions
Is GPT-6 Sol out?
Yes. OpenAI released it on Tuesday 22 September 2026. It is in the API as gpt-6-sol and rolling out in ChatGPT Work and Codex on the Plus, Pro, Business, Enterprise and Edu plans.
How much does GPT-6 Sol cost?
In the API, $2 per million input tokens and $10 per million output tokens, with cached input at $0.20. Prompts above 272,000 input tokens are billed at twice the input rate and 1.5 times the output rate. In ChatGPT it comes with the Plus plan and above.
Is GPT-6 Sol the same as GPT-5.6 Sol?
No. They share a tier, one generation apart. GPT-5.6 Sol came out on 9 July 2026 and GPT-6 Sol on 22 September 2026, at half GPT-5.6 Sol's promotional price.
Is GPT-6 Sol better than GPT-6 Astra?
No. OpenAI calls Astra its best model across the board, and Artificial Analysis scores Astra 53 against Sol's 48 at max effort. Sol is faster and costs a fifth as much per token.
Can I use GPT-6 Sol for free in ChatGPT?
No. Free and Go users get GPT-6 Luna, in the desktop app. GPT-6 Sol is on the paid plans, in ChatGPT Work and Codex for now.
Is there a GPT-6 Terra?
Not yet. OpenAI launched Sol and Luna on 22 September and has not announced a GPT-6 model for the Terra tier. GPT-5.6 Terra remains available.
Update log
22 September 2026, 21:30 UTC. OpenAI released GPT-6 Sol and GPT-6 Luna. Tracker scored against the launch post, the model pages and the API pricing page. Added launch facts and Artificial Analysis scores.
21 September 2026, 20:22 UTC. Page opened. No gpt-6-sol in OpenAI's API, developer docs, pricing page or ChatGPT help centre.