# GPT-6 Sol

> OpenAI's balanced GPT-6 tier for complex coding and agentic workflows, at half the price of GPT-5.6 Sol.

- Maker: OpenAI
- Line: GPT (Flagship / Thinking)
- Canonical page: https://ai-tldr.dev/models/gpt-6-sol/
- Updated: 2026-09-29

## In short

GPT-6 Sol is the balanced tier of OpenAI's GPT-6 family, released on September 22, 2026 alongside the low-cost GPT-6 Luna. It has a 1.05M-token context window and costs $2.00 per million input tokens and $10.00 per million output tokens. You can use it through OpenAI API.

## Facts

| Fact | Value | Source |
| --- | --- | --- |
| Context window | 1.05M (max output 128K) | [1] |
| Input price | $2.00 / 1M tokens (cached $0.20) | [2] |
| Output price | $10.00 / 1M tokens | [2] |
| Licence | Proprietary · API only | [1] |
| Released | 22 September 2026 | [3] |
| Knowledge cutoff | 20 April 2026 | [1] |

## Sources

1. [GPT-6 Sol model documentation](https://developers.openai.com/api/docs/models/gpt-6-sol)
2. [OpenAI API pricing (GPT-6 Sol rates)](https://developers.openai.com/api/docs/pricing)
3. [OpenAI's GPT-6 Sol and GPT-6 Luna now available (GitHub Copilot changelog)](https://github.blog/changelog/2026-09-22-openais-gpt-6-sol-and-gpt-6-luna-now-available/)

## Overview

GPT-6 Sol is the balanced tier of OpenAI's GPT-6 family, released on September 22, 2026 alongside the low-cost GPT-6 Luna. OpenAI's API documentation describes it as "Built for complex coding and agentic workflows", and GitHub's Copilot changelog calls it "a balanced model for interactive and agentic coding" suited to development work that benefits from careful, multistep validation. Until this release, GPT-6 meant only Astra, the top tier.

Sol accepts text and image input and returns text, with a 1,050,000-token context window and up to 128,000 output tokens. Its knowledge cutoff is April 20, 2026. It is served on the Chat Completions and Batch endpoints and supports streaming, structured outputs, function calling, file search, image input, web search, and prompt caching. Reasoning effort is configurable across none, low, medium, high, xhigh, and max.

The headline change is price. OpenAI lists GPT-6 Sol at $2.00 per 1M input tokens, $0.20 per 1M cached input tokens, and $10.00 per 1M output tokens — exactly half the $4.00 / $0.40 / $20.00 that GPT-5.6 Sol carries. Requests that run past the short-context limit are billed at the long-context rates of $4.00 input, $0.40 cached input, and $15.00 output per 1M tokens.

OpenAI positions Sol as reaching the reliability of the far more expensive Astra tier at much lower cost, reporting that GPT-6 Sol makes about half as many mistakes as its predecessor. At launch the model was available in the ChatGPT API, Codex, and ChatGPT Work, and GitHub added it to Copilot the same day for Pro+, Max, Business, and Enterprise plans across VS Code, Visual Studio, the Copilot CLI, the cloud agent, github.com, mobile, JetBrains, Xcode, and Eclipse.

## Pricing

- Input: $2.00 / 1M tokens
- Cached input: $0.20 / 1M tokens
- Output: $10.00 / 1M tokens

Half the GPT-5.6 Sol rate of $4.00 input / $20.00 output. Long-context requests are billed at $4.00 input, $0.40 cached input and $15.00 output per 1M tokens. Regional data residency endpoints carry a 10% surcharge.

Source: https://developers.openai.com/api/docs/pricing

## Strengths

- Half the token price of GPT-5.6 Sol on both input and output
- 1.05M-token context window, matching the top GPT-6 Astra tier
- Configurable reasoning effort from none through max
- Built for interactive and agentic coding with multistep validation
- Prompt caching at $0.20 per 1M tokens, a tenth of the input rate

## Best for

- Reach for it for agentic coding loops where per-token cost decides how much the agent can attempt.
- Reach for it when a job needs long-context reading but not the price of the Astra tier.
- Reach for it in GitHub Copilot on Pro+, Max, Business, or Enterprise for day-to-day development work.
- Reach for it for high-volume batch jobs, which the Batch endpoint supports directly.

## How to access

- [OpenAI API](https://developers.openai.com/api/docs/models/gpt-6-sol) — model id `gpt-6-sol`

## GPT (Flagship / Thinking) versions

- GPT-6.1 Sol (29 September 2026) — this page
- [GPT-6 Sol](https://ai-tldr.dev/models/gpt-6-sol/) (22 September 2026): Released alongside GPT-6 Luna at half the GPT-5.6 Sol token price.
- [GPT-5.6 Sol](https://ai-tldr.dev/models/gpt-5-6-sol/) (9 July 2026)
- [GPT-5.5](https://ai-tldr.dev/models/gpt-5-5/) (23 April 2026)
- [GPT-5.4](https://ai-tldr.dev/models/gpt-5-4/) (5 March 2026)

## FAQ

### How much does GPT-6 Sol cost?

OpenAI lists GPT-6 Sol at $2.00 per 1M input tokens, $0.20 per 1M cached input tokens, and $10.00 per 1M output tokens. That is exactly half the GPT-5.6 Sol rate of $4.00 input and $20.00 output. Requests past the short-context limit are billed at the long-context rates of $4.00 input, $0.40 cached input, and $15.00 output.

### How large is the GPT-6 Sol context window?

GPT-6 Sol has a 1,050,000-token context window with a maximum of 128,000 output tokens, the same as GPT-6 Astra and GPT-6 Luna. Its knowledge cutoff is April 20, 2026. Reading past the short-context limit moves the request onto OpenAI's long-context pricing.

### How does GPT-6 Sol compare to GPT-6 Astra?

GPT-6 Astra remains the top tier at $10.00 input and $50.00 output per 1M tokens, five times Sol's price. Both share the 1.05M-token context window and 128K output limit, so the difference is capability and cost rather than how much they can read. OpenAI says GPT-6 Sol reaches Astra-level reliability at much lower cost.

### Where can I use GPT-6 Sol?

GPT-6 Sol is available in the ChatGPT API, Codex, and ChatGPT Work. GitHub also added it to Copilot on release day for Pro+, Max, Business, and Enterprise plans, rolling out across VS Code, Visual Studio, the Copilot CLI, the cloud agent, github.com, mobile, JetBrains, Xcode, and Eclipse.

### Which features does the GPT-6 Sol API support?

OpenAI's documentation lists streaming, structured outputs, function calling, file search, image input, web search, and prompt caching for GPT-6 Sol, served on the Chat Completions and Batch endpoints. The model accepts text and image input and returns text, and its reasoning effort can be set to none, low, medium, high, xhigh, or max.

## Links

- [GPT-6 Sol model documentation](https://developers.openai.com/api/docs/models/gpt-6-sol)
- [OpenAI API pricing (GPT-6 Sol rates)](https://developers.openai.com/api/docs/pricing)
- [OpenAI launches GPT-6 Sol and Luna (TechCrunch, September 22, 2026)](https://techcrunch.com/2026/09/22/openai-launches-gpt-6-sol-and-luna/)
- [OpenAI's GPT-6 Sol and GPT-6 Luna now available (GitHub Copilot changelog)](https://github.blog/changelog/2026-09-22-openais-gpt-6-sol-and-gpt-6-luna-now-available/)

Source: AI/TLDR LLM registry, https://ai-tldr.dev/models/gpt-6-sol/