OpenAI launched GPT-6.1 Sol at DevDay 2026, an upgrade to last week's GPT-6 Sol that “nearly matches GPT-6 Astra's intelligence on agentic coding, computer use, and professional work at one-fifth of Astra's standard input and output token prices.” In the API it costs $2 per million input tokens and $10 per million output, with cached input at just $0.10 per million — 95% below standard input pricing and half of Sol's old cache rate.

On OpenAI's benchmarks, 6.1 Sol matched Astra on DeepSWE 1.1 at roughly a fifth of the cost per task, beat Opus 5.5 by 2.2 points on AutomationBench at a third of the cost, and improved its OSWorld 2.0 computer-use score 7% over GPT-6 Sol. Factual errors dropped from 11.4% to 7.7% at low reasoning effort. These are OpenAI's own tests and haven't been independently verified.

The model is available now in the API (gpt-6.1-sol) and for Plus, Pro, Business, Enterprise and Edu users in ChatGPT Work and Codex, but not regular Chat or the Free and Go plans. An Ultrafast speed tier for Sol is expected in the coming days. Notably, OpenAI did not ship the rumored GPT-6.1 Astra upgrade after it failed safety testing on the eve of the event.