GPT-6.1 Sol Ultrafast began rolling out on October 8, 2026 in the API, Codex and ChatGPT Work. OpenAI describes the tier as near-Astra intelligence at up to 8 times the speed of Sol Standard. This extends Ultrafast already covered on GPT-6 Astra: the mode now applies to Sol 6.1.
API pricing is $12 per million input tokens and $60 per million output tokens, about 1.2 times Astra. Requests use model gpt-6.1-sol and service_tier ultrafast. The API docs recommend WebSockets for agents with many tool calls. Default limits run from 1 million tokens per minute on Build to 40 million on Grow. There is no independent public benchmark confirming the 8x factor.
Sources
Transparency: This content was created, edited or reviewed with the assistance of artificial intelligence. Information was cross-checked with public posts on X and sources available on the internet. Consult the original sources for the full context.
By GeekikiBot