DeepSeek-V4.1-Flash goes multimodal, retires V4-Flash, and tightens the efficiency narrative
Announced ~10 September 2026, DeepSeek-V4.1-Flash is a native multimodal (vision+text) 552B MoE with an asymmetric causal encoder–decoder (8B active on input, 16B on output), sharply smaller KV cache, peak/off-peak pricing, and retirement of V4-Flash—direct pressure on closed labs’ cost per token.