DeepSeek V4.1 Flash is a sparse mixture-of-experts model from DeepSeek, and the cost-efficient tier of the V4.1 family. DeepSeek reports that it exceeds V4 Pro on performance, speed, and task completion time, so it sits ahead of the previous flagship rather than beneath it. It is suited for coding, reasoning, and agentic workflows, and is particularly strong at long-horizon tasks that must run to completion across many steps.