What Is GPT-6.1 Sol? What Do Its Price and Performance Offer?
GPT-6.1 Sol is OpenAI's new model, delivering performance close to GPT-6 Astra at one-fifth of the price.
GPT-6.1 Sol is the new AI model OpenAI released on September 29, 2026. It delivers performance close to the GPT-6 Astra level at one-fifth of the price. It stands out for businesses in coding, computer-use tasks, and professional workflows.
In short:
- GPT-6.1 Sol pricing: $2/million input, $10/million output tokens; one-fifth of Astra's price.
- Performs at the same level as Astra on the DeepSWE v1.1 benchmark.
- Scores 7 points higher than GPT-6 Sol on OSWorld 2.0, at less than half the cost.
- Available to Plus, Pro, Business, Enterprise, and Edu users in ChatGPT Work and Codex.
What is GPT-6.1 Sol?
This new model is OpenAI's latest mid-tier product in the GPT-6 family. Its goal is to deliver performance close to GPT-6 Astra's power at a much more affordable price. The company is positioning this product specifically for coding, computer-use tasks, and professional workflows (openai.com).
As the name suggests, this is an improved version of GPT-6 Sol and Luna, which was announced at the beginning of September. This update, arriving in less than a week, shows OpenAI's rapid iteration strategy.
The API call name has been set as gpt-6.1-sol. Developers can easily update their existing integrations.
How much does GPT-6.1 Sol cost?
Pricing is set at $2 per million input tokens and $10 per million output tokens. By comparison, GPT-6 Astra carries a pricing of $10 for input and $50 for output (openai.com).
For input tokens read from the cache, the price is $0.10/million. Cache write operations are priced at $2.50/million tokens (developers.openai.com).
The model has a massive context window of 1,050,000 tokens. Maximum output is capped at 128,000 tokens. Its knowledge cutoff date is April 30, 2026.
This price advantage matters for businesses that want Astra-level results but face budget constraints. The new model creates a significant difference in the cost-performance balance.
How did GPT-6.1 Sol perform in benchmark tests?
On the DeepSWE v1.1 software engineering benchmark, it scored at the same level as GPT-6 Astra (openai.com). This means quality very close to Astra on real coding tasks.
On OSWorld 2.0 computer-use tasks, it scored 7 points higher than the previous version. Moreover, this was achieved at less than half the cost.
The compounding error rate in low-effort mode also improved. The rate dropped from 11.4% to 7.7%, roughly a 32% improvement.
On the Terminal-Bench Science 0.1 test, the average task cost is notable. For the new model, this cost is $5.47. By comparison, the Opus 5.5 model spends $23.21, and GPT-6 Astra spends $23.80.
| GPT-6.1 Sol | 5,47 |
|---|---|
| Claude Opus 5.5 | 23,21 |
| GPT-6 Astra | 23,80 |
Kaynak: OpenAI
The numbers speak clearly: the new model runs nearly four times cheaper on similar tasks. This difference translates into significant savings for teams with heavy usage.
On the GDP.pdf test, it performed better than Opus 5.5. This was achieved at less than half the cost. On AutomationBench, it achieved similar results with a 2.2-point difference at one-third the price.
For those who want to compare these results with the price-performance data in our Claude Opus 5.5 article, this offers a different perspective.
Where can GPT-6.1 Sol be used?
This model is available to Plus, Pro, Business, Enterprise, and Edu users. It can be used in ChatGPT Work and Codex environments.
For developers, the supported effort levels are as follows: low, medium (default), high, xhigh, and maximum. The none and minimal levels are not supported for this model (developers.openai.com).
An Ultrafast version is also coming for Codex. This version promises a token generation speed 8 times faster than the standard speed. It is expected to become available soon.
What is the difference between GPT-6.1 Sol and GPT-6 Astra?
GPT-6 Astra, in fact, was not released as initially expected. Researchers delayed its release due to safety concerns (techcrunch.com).
This delay played a role in OpenAI highlighting its new product. The company offered users a model close to Astra's power but more controlled.
In this context, a practical solution emerges in terms of both cost and accessibility. Businesses can get similar-quality results without waiting for Astra.
Such model delays are common in the industry. We touched on a similar process in our Gemini 4 Pro leaks article.
Frequently asked questions
What is GPT-6.1 Sol used for?
It's used for coding, computer-use, and professional work tasks. It offers intelligence close to the GPT-6 Astra level at one-fifth of Astra's price.
What is the difference between GPT-6.1 Sol and GPT-6 Sol?
On the DeepSWE v1.1 benchmark, it scored 6.4 points higher than GPT-6 Sol. This was achieved with less effort and at a lower cost.
Which ChatGPT plans can use it?
GPT-6.1 Sol is available to Plus, Pro, Business, Enterprise, and Edu users. It can be accessed through the ChatGPT Work and Codex interfaces.
Is there a faster version?
Yes, GPT-6.1 Sol Ultrafast is coming soon. This version promises token generation 8 times faster than the standard speed.
GPT-6.1 Sol offers an attractive option for businesses with its price-performance balance. When deciding which model and architecture your software team should move forward with, you can benefit from EngerekTech's enterprise software experience.
