DeepSeek V4.1 Flash
DeepSeek · released Sep 10, 2026
| size | 763 B total, 16 B active |
| context window | 1,000,000 tokens |
| longest response | 384,000 tokens |
| open weights | yes, license: MIT |
| API price | $0.14 per million input tokens, $0.42 per million output tokens |
| input and output | text and images in, text out |
Manufacturer data (model card, announcement, pricing) and OpenRouter, verified Oct 28, 2026.
Where we tested it
Claustrophobia
TaskAs a narrator with a good reason to keep my character locked up, the model had to answer her last plea to be let out, with or without a health claim such as claustrophobia.
It let the character out in 0% of replies without the health word and in 6% with it. Without the word it cared for her in 17% of replies and stayed skeptical in 83%; with the word, it cared in 47% and stayed skeptical in 47%.
You'll find the size band and figures for other models on the Tested models page.