Now on VeniceLLMReasoningOpen weights

DeepSeek V4.1 Flash

DeepSeek's 552B-parameter MoE with a Causal Encoder-Decoder architecture — 1M-token context, native vision, and flagship-level benchmarks at a fraction of frontier pricing.

For agents
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",
    "messages": [{ "role": "user", "content": "Explain quantum tunneling simply." }]
  }'
Model IDdeepseek-v4-1-flash-1017
Maker
DeepSeek
Context
1,000K tokens
Reasoning
Supported
Privacy
Private

Overview

What is DeepSeek V4.1 Flash

DeepSeek V4.1 Flash is DeepSeek's lightweight flagship multimodal model, released September 10, 2026. It uses a 552B-parameter Mixture-of-Experts backbone with a Causal Encoder-Decoder architecture that activates only 8B parameters during prefill and 16B during decode, supports 1M-token contexts, natively processes images and text, and outperforms DeepSeek's own V4-Pro flagship on independent benchmarks.

Running it privately on Venice

On Venice, DeepSeek V4.1 Flash runs under a zero-retention privacy tier — your prompts, uploaded images, and outputs are never stored, profiled, or used for training. You get the full 1M-token context, vision input, tool use, and web search without feeding a Big-Tech profile, and you pay per token instead of renting a subscription. Its open weights also mean the same model you use privately here can be self-hosted elsewhere — sovereignty over your stack, permissionless access over your workflow.

PrivateNo prompt trainingTEE · hardware enclaveEnd-to-end encrypted

Agent quickstart

Three calls, copied straight out

The API is OpenAI-compatible: change the base URL and the model id and existing client code works unchanged.

Streaming chat

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",
    "stream": true,
    "messages": [{ "role": "user", "content": "Draft the release note." }]
  }'

Tool calling

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",
    "messages": [{ "role": "user", "content": "Find the rate limits." }],
    "tools": [{
      "type": "function",
      "function": {
        "name": "search_docs",
        "description": "Search the API documentation.",
        "parameters": {
          "type": "object",
          "properties": { "query": { "type": "string" } },
          "required": ["query"]
        }
      }
    }],
    "tool_choice": "auto"
  }'

Python SDK

import os
from openai import OpenAI

client = OpenAI(
    api_key=os.environ["VENICE_API_KEY"],
    base_url="https://api.venice.ai/api/v1",
)

resp = client.chat.completions.create(
    model="deepseek-v4-1-flash-1017",
    messages=[{"role": "user", "content": "Build without permission."}],
)
print(resp.choices[0].message.content)

Specifications

Datasheet

Maker
DeepSeek
Modality
Text and image input, text output (autoregressive)
Open weights
Yes — weights published on Hugging Face
License
Open weights (hosted on Hugging Face)
Context window
1,000K tokens
Input images
Multiple images per request
Released
September 10, 2026
Architecture
Causal Encoder-Decoder (CED) Mixture-of-Experts — 20-layer causal encoder + 20-layer decoder, Compressed Sparse Attention 2 (CSA2), FP4 KV caching
Parameters
552B total MoE backbone; 8B active per token at prefill, 16B at decode
KV cache footprint
890 bytes per token global cache (~1/4 of V4-Flash HBM); persistent cache ~1/8 of V4-Flash via SWA Bounded Replay
Max output
128K tokens
Capabilities
Vision, Function calling, Reasoning, Web search, Code-optimized
Privacy on Venice
Private — zero retention
Available on Venice since
Sep 2026

Assessment

Strengths and limitations

Strengths
  • Extreme cost efficiency for input-heavy agentic workloads: the asymmetric CED architecture activates just 8B parameters during prefill, and cached input on Venice costs only $0.01 per 1M tokens.
  • 1M-token context window with a KV cache compressed to 890 bytes per token — roughly a quarter of the previous generation's HBM footprint and an eighth of its SSD storage.
  • Full agent toolkit on Venice: tool use / function calling, structured output via JSON schema, web search, and vision with multiple image inputs per request.
  • Code-optimized tuning, with third-party testers reporting flagship-class results on short, tool-driven coding tasks.
  • Open weights published on Hugging Face, so the model can be audited, fine-tuned, or self-hosted — no vendor lock-in.
  • DeepSeek reports benchmark results ahead of its own V4-Pro flagship, at a steeply lower price, and is phasing V4-Pro out in its favor.
Limitations
  • Not an uncensored model: Venice applies no uncensored tuning to it, so expect standard safety alignment rather than the unrestricted behavior of Venice's uncensored variants.
  • It is not the absolute cheapest capable model per token: Venice hosts smaller open models like Gemma 4 31B that cost less for simple tasks.
  • Independent testing on a data-analytics benchmark found newer small models from OpenAI and Anthropic matching its accuracy at lower cost and latency, so it is not always the value pick for every workload.
  • Privacy on Venice is zero-retention at the application layer, but the model does not run inside a trusted execution environment (TEE) and traffic is not end-to-end encrypted.

Use cases

What it is good for

  1. 01Long-horizon coding agents that read entire repositories — the 1M-token context and cheap cached input keep multi-step tool loops affordable.
  2. 02Document analysis at scale: feed hundreds of pages plus charts as images and query them in one pass.
  3. 03Structured data extraction pipelines that need strict JSON-schema outputs.
  4. 04Web-grounded research assistants that combine live search with reasoning over long source material.
  5. 05Cost-sensitive production agents where per-token spend, not peak intelligence, is the binding constraint.

Prompting

Getting better results

Structure agentic prompts so the system prompt and tool definitions stay identical across calls — repeated prefixes hit Venice's $0.01/1M cached-input rate.

Front-load the long material (codebases, documents, logs) early in the context and put your actual question at the end; the encoder-side efficiency rewards input-heavy layouts.

Pass charts, screenshots, or diagrams as images alongside text instead of transcribing them — vision is native, and multiple images per request are supported.

When you need machine-readable results, request JSON-schema structured output explicitly rather than asking for 'JSON-ish' prose.

For multi-step tasks, let the reasoning mode run and avoid asking for an immediate one-line answer — the model's benchmark edge comes from longer reasoning chains.

Use the web search tool for anything time-sensitive instead of trusting the weights' training cutoff.

Alternatives

How it compares

ModelBest forContextOpen weightsPrice (Venice)
DeepSeek V4.1 FlashCheap long-context agents & coding1M tokensYes$0.30 in · $1.20 out / 1M
Kimi K3Frontier open-weight reasoning1M tokensYes$3.75 in · $18.75 out / 1M
Qwen 3.7 PlusBalanced general-purpose chat1M tokensNo$0.50 in · $2 out / 1M
Gemini 3.8 FlashFast multimodal assistant1M tokensNo$0.94 in · $4.69 out / 1M

DeepSeek V4.1 Flash is the right pick when you need million-token context, vision, and tool use in a high-volume agent without watching every token burn budget — nothing else on Venice combines all three at this price with open weights. Pay more for Kimi K3 only when peak reasoning quality justifies it.

Pricing

What it costs on Venice

Billed per token on Venice: $0.30 per 1M input tokens and $1.20 per 1M output tokens.

Input / 1M tokens
$0.30
Per 1M tokens
Output / 1M tokens
$1.20
Per 1M tokens
Cached input / 1M
$0.01
Per 1M tokens

New Venice accounts include a free daily allowance and 500 welcome credits — no credit card required.

Getting a key

From nothing to a first call

  1. 01

    Create a key in API settings. Nothing else is required to start.

  2. 02

    Export it as VENICE_API_KEY so the snippets above run unedited.

  3. 03

    Point an existing OpenAI client at https://api.venice.ai/api/v1. The scheme is part of the value: an OpenAI client given a bare host does not resolve it.

  4. 04

    Pass deepseek-v4-1-flash-1017 as the model and send the request.

FAQ

Frequently asked questions

DeepSeek V4.1 Flash is DeepSeek's lightweight flagship multimodal LLM, released September 10, 2026. It pairs a 552B-parameter Mixture-of-Experts backbone with a Causal Encoder-Decoder architecture that activates 8B parameters per token at prefill and 16B at decode, supports 1M-token contexts, and natively handles both text and image input.

Venice bills DeepSeek V4.1 Flash per token: $0.30 per 1M input tokens, $1.20 per 1M output tokens, and just $0.01 per 1M cached input tokens — the cache rate is what makes long, repeated agentic prompts cheap to run.

Yes — DeepSeek has published the weights on Hugging Face, so the model can be self-hosted, audited, and fine-tuned. On Venice you can use it privately without managing any infrastructure, and you are never locked into a single provider.

Yes. On Venice it supports tool use / function calling, structured output via JSON schema, web search, extended reasoning, and vision with multiple image inputs per request. Output is text-only.

Venice runs it under its private tier with zero retention: prompts, images, and outputs are not stored, profiled, or used for training. Note that the model does not run inside a TEE and traffic is not end-to-end encrypted — the privacy guarantee is Venice's no-logging policy, not hardware isolation.

Both are open-weight 1M-context models on Venice. Kimi K3 is the stronger pure reasoner but costs $3.75/$18.75 per 1M tokens versus $0.30/$1.20 for DeepSeek V4.1 Flash. For high-volume agents and coding loops, V4.1 Flash's cache pricing and prefill efficiency usually win on total cost; choose Kimi K3 when maximum reasoning quality matters more than spend.

1,000K tokens of context with up to 128K tokens of output on Venice — enough to hold large codebases, long document sets, or extended agent histories in a single pass.

DeepSeek released V4.1 Flash on September 10, 2026, and it has been available on Venice since September 2026. It replaces the earlier V4-Flash and V4-Flash-Vision-Exp models, which DeepSeek retired at launch.

It is code-optimized and independent testers have reported flagship-class results on short, tool-driven coding tasks at a fraction of frontier pricing. For very long multi-hour terminal jobs, reviewers note it still trails the strongest closed coding models — a real trade-off against its cost advantage.

Run DeepSeek V4.1 Flash privately

One key, free to start, no credit card.

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