DeepSeek V4.1 Flash 1017 Ultrafast API

DeepSeek V4.1 Flash 1017 Ultrafast is a large language model by DeepSeek, available on the Venice API as deepseek-v4-1-flash-1017-ultrafast. It runs privately, with zero data retention.DeepSeek V4.1 Flash is a multimodal Mixture-of-Experts model with 552B backbone parameters (8B active on input, 16B on output) and a 1M-token context window. It natively processes images and text, with strong reasoning, coding, and agentic performance.

DeepSeek V4.1 Flash 1017 Ultrafast API pricing

Model ID	Variant	Privacy	Price
`deepseek-v4-1-flash-1017-ultrafast`	Standard	Private	$3.00 / $12.00 per 1M

DeepSeek V4.1 Flash 1017 Ultrafast specifications

Spec	Value
Provider	DeepSeek
Released	Oct 23, 2026
Privacy	Private
Status	Stable
Open weights	Yes
Context window	1M tokens
Max output	128K tokens
Reasoning effort	none, low, high, max
Served precision	FP8

How to use the DeepSeek V4.1 Flash 1017 Ultrafast API

Send requests to POST https://api.venice.ai/api/v1/chat/completions with "model": "deepseek-v4-1-flash-1017-ultrafast" and your API key.

curl https://api.venice.ai/api/v1/chat/completions \
  -H "Authorization: Bearer $VENICE_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "deepseek-v4-1-flash-1017-ultrafast",
    "messages": [{ "role": "user", "content": "Explain TEE attestation in two sentences." }],
    "reasoning_effort": "high"
  }'

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