OpenAI Unveils 'Ultrafast' Engine Running GPT-5.6 Sol at 14x Inference Speed

OpenAI has officially launched 'Ultrafast' mode across its API and ChatGPT Enterprise suites for the GPT-5.6 Sol model family. The upgraded engine delivers a staggering 14x increase in token generation throughput while cutting response latency down to single-digit milliseconds.

Sub-20ms Token Latency: Architectural Innovation in Speculative Decoding and Compute Kernels

Achieved through custom hardware kernel optimizations, speculative draft model orchestration, and memory bandwidth streaming enhancements, Ultrafast mode eliminates the friction historically plaguing long-context reasoning models during multi-step execution.

Unlocking Real-Time Multimodal Voice and Ultra-Responsive Autonomous Coding Agents

Developers can now build voice interfaces that converse with zero perceptible pause and autonomous software agents that execute hundreds of test-compile loops per minute, opening up unprecedented possibilities for automated workflows.