Large language model
GPT-6.1 Sol
GPT-6.1 Sol is a reasoning model released by OpenAI on 29 September 2026 at its DevDay event. It follows GPT-6 Sol in the GPT-6 family, has a 1,050,000-token context window and is aimed at complex coding, computer use and professional work at one-fifth of GPT-6 Astra's standard token prices.
Last reviewed 28 Oct 2026 · by OpenAI
Facts at a glance
| Developer | OpenAI |
|---|---|
| Released | 29 September 2026 source |
| API name | gpt-6.1-sol source |
| Context window | 1,050,000 tokens (922,000 max input) source |
| Max output | 128,000 tokens source |
| Knowledge cutoff | 30 April 2026 source |
| API price | $2 per 1M input tokens, $0.10 cached input, $2.50 cache writes, $10 per 1M output tokens source |
| Preparedness Framework | Treated as Critical in cybersecurity and High in biological and chemical capability source |
What GPT-6.1 Sol is used for
OpenAI says GPT-6.1 Sol delivers near-Astra performance at a lower cost for complex coding, computer use and professional work. Reasoning effort runs from low to max with medium as the default; the none level is not supported. Tool calling requires the Responses API, where the model also supports multi-agent delegation in beta. Fine-tuning is not supported. Since 8 October 2026 it can also run in the paid Ultrafast tier, which OpenAI prices at six times the standard rate.
Questions people ask
- When was GPT-6.1 Sol released?
- OpenAI released it on 29 September 2026, the day of DevDay 2026, according to the API changelog.
- How much does GPT-6.1 Sol cost?
- $2 per million input tokens and $10 per million output tokens at the standard rate, with cached input at $0.10 per million.
- How does GPT-6.1 Sol differ from GPT-6 Sol?
- It keeps GPT-6 Sol's $2 input and $10 output prices but halves cached input from $0.20 to $0.10 per million tokens, and OpenAI reports higher coding and computer-use scores.