DeepSeek launches DeepSeek‑V4.1‑Flash with new causal encoder–decoder and lower costs
DeepSeek announced DeepSeek‑V4.1‑Flash, a smaller-native-vision model using a new Causal Encoder–Decoder design (8B active params for input, 16B for output), new pretraining and larger-scale RL post-training, plus KV‑cache compression. The company is retiring V4‑Flash variants, routing deepseek-v4-pro traffic to V4.1‑Flash from 04:00 UTC on Sept 14, 2026, and changing pricing (new rates take effect 04:00 UTC on Sept 10, 2026) while partners WorkBuddy, CodeBuddy and OpenCode already support V4.1‑Flash.