DeepSeek V4.1 Flash internal beta needs no sign-up! Just change the model name to jump right in

Technology and Creation AI
1

Flash Update: DeepSeek has quietly opened internal testing for an intermediate V4.1 Flash release.

No application or form required — just change the model name and you can use it.

Key Information

Item Details
Model name deepseek-v4.1-flash-expires-on-0910
base_url Unchanged — use the original one
Pricing Same as deepseek-v4-flash
Concurrency limit 20 concurrent requests per account (Note: the official release allows 2,500; the internal test version is heavily rate-limited)
Expiration As the name suggests, expires on September 10 — try it while you can

How do you get started?

Just change the model name used in your code to the one above:

cURL example

curl https://api.deepseek.com/v1/chat/completions \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer $DEEPSEEK_API_KEY" \
  -d '{
    "model": "deepseek-v4.1-flash-expires-on-0910",
    "messages": [{"role": "user", "content": "你好"}]
  }'

Python (OpenAI SDK)

from openai import OpenAI

client = OpenAI(
    api_key="你的API_KEY",
    base_url="https://api.deepseek.com/v1"
)

response = client.chat.completions.create(
    model="deepseek-v4.1-flash-expires-on-0910",  # Just change this line
    messages=[{"role": "user", "content": "介绍一下新模型"}]
)

What’s different about the new model?

According to the official description, it features a new model architecture and native multimodal support, making it more capable, faster, and cheaper. We’ll have to wait for everyone’s hands-on testing and feedback for the specific results.

Notes

  1. This is a time-limited test endpoint that expires on September 10, so don’t hard-code it into production environments
  2. With a 20-request concurrency limit, it’s fine for testing, but don’t use it for large-scale batch jobs
  3. The official documentation hasn’t been updated with a formal release record yet — it’s essentially a „sneak preview within the group“

Looking forward to everyone’s in-depth reviews — let’s see just how fast this version of Flash really is :eyes: