OpenAI Ultrafast API docs leak, promising up to 14x faster processing

Documents related to Ultrafast API have appeared in OpenAI Platform and API docs, suggesting the company may be preparing to expand access to this API. The feature is currently hidden.

OpenAI is preparing new speed options for the Responses API Playground, letting users choose between Standard, Fast, and Ultrafast processing speeds. OpenAI previously previewed the Ultrafast mode with GPT-5.6 Sol, saying it can output up to 750 tokens per second, up to 14 times faster than Standard mode. The mode is still only available to select customers.

Based on timing, it's possible Ultrafast will expand during the DevDay on September 29. OpenAI has already launched the GPT-6 series, including GPT-6 Sol and GPT-6 Astra. Whether these new models support Ultrafast is worth watching.