DeepSeek LLM Big Open weights

DeepSeek V4.1 Flash

63 days since DeepSeek announced it · 10 Sep 2026

DeepSeek V4.1 Flash is an open-weights LLM from DeepSeek, announced 10 Sep 2026. It costs $0.30 per 1M input tokens and $1.20 per 1M output tokens. Its context window is 1M tokens. It has 552B parameters.

Input: $0.30; per 1M tokens
Cache write: —; per 1M tokens
Cache read: $0.01; per 1M tokens
Output: $1.20; per 1M tokens
Context window: 1M; tokens
Parameters: 552B; total

Announcement: api-docs.deepseek.com/news/news260910

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DeepSeek · Big · Flash

open weights

A new one every ~139 days — due in ~113d.

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