DeepSeek V4.1 Flash: beats V4 Pro on benchmarks, cuts API price, and goes open source

DeepSeek V4.1 Flash: Stronger, Faster, More Accessible

DeepSeek released V4.1 Flash, a 552B MoE model that activates only 8B params on input and 16B on output. It uses a new asymmetric Causal-Encoder-Decoder architecture and scores above DeepSeek V4 Pro on benchmarks. KV cache size drops to 1/4 HBM and 1/8 SSD vs the previous gen, cutting agent-scenario cache costs. The API is live under model name deepseek-flash; V4 Pro will be routed to V4.1 Flash from Sep 14 noon Beijing time and billed at Flash pricing. New peak/off-peak prices start Sep 10 noon, with off-peak at half rate. Weights and a tech report are open on HuggingFace; DeepSeek invites contact for large-scale deployments needing a 2k-GPU cluster.

Why it matters: DeepSeek flagship model release with architectural change and concrete perf/cost numbers — policy treats this on par with US lab launches. All three HKR axes hit: the V4 Pro-beating score and cache shrinkage are hard info. Held back from P1 because only title + summary availab...