OpenAI Ultrafast: 750 Tokens/s Ends the Fast-vs-Smart Tradeoff
On August 13, 2026, OpenAI previewed Ultrafast, a serving tier that streams GPT-5.6 Sol at up to 750 output tokens per second on Cerebras wafer-scale engines, with up to 14x the throughput of the Standard tier. Cerebras-reported benchmarks put it ~11x faster than Claude Fable 5 and ~5x faster than Claude Opus 4.8 Fast, with a 5.6x end-to-end speedup on GDP-Val. We break down the latency-budget math of multi-hop agent loops, the ROI for support and incident-response agents, and the API code for benchmarking the new service tier. All figures are vendor-reported preview data.