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DeepSeek V4.1 Flash 1017

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DeepSeekReleased Oct 17, 2026deepseek/deepseek-v4.1-flash-1017
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DeepSeek-V4.1-Flash-1017 is the October 17, 2026 update to DeepSeek-V4.1-Flash, a multimodal Mixture-of-Experts model that natively accepts text and images, with a 1M-token context window and MIT license. It improves reasoning, coding, agentic tasks, and visual benchmarks over V4.1 Flash while reducing task execution time and output length, so tasks finish faster and cheaper. DeepInfra serves it in fp8 with JSON output, function calling, and zero data retention, plus Priority and Flex service tiers. DeepSeek reports DeepSWE v1.1 at 77.0 (up from 74.2) and Terminal-Bench 4.0 at 42.3 (up from 31.2) versus V4.1 Flash.

Context
1.05M
Max output
944K
Input /1M
$0.10
Output /1M
$0.29
Blended /1M
$0.15
AcceptsTextImageProducesTextInstruct type none

Providers

4 providers serve this model. FastRouter routes each request to the best available one, and you can bring your own key for any of them.

Pricing tier
DeepInfra logo
DeepInfrafp8Cheapest
deepinfra
Input /1M$0.10
Output /1M$0.29
Context1.05M
Max output131K
Latency—
Throughput—
Supports tool callingSupports structured (JSON) output
Baseten logo
Baseten
baseten
Input /1M$0.30
Output /1M$1.20
Context1.05M
Max output944K
Latency—
Throughput—
Supports tool calling
Together AI logo
Together AI
together
Input /1M$0.30
Output /1M$1.20
Context1.05M
Max output944K
Latency—
Throughput—
Supports tool calling
Alibaba logo
Alibaba
alibaba
Input /1M$0.30
Output /1M$1.20
Context1.05M
Max output944K
Latency—
Throughput—
Supports tool calling

Supported parameters

Request parameters you can send with this model.

Parameter
Type
DeepInfra
Baseten
Together AI
Alibaba
Core (Sampling & basic generation)
max_tokensMaximum tokens to generate.
number
1 to 131072
1 to 4096
1 to 4096
1 to 4096
temperatureControls randomness of output.
number
0 to 2
0 to 2
0 to 2
0 to 2
top_pNucleus sampling threshold.
number
0 to 1
0 to 1
0 to 1
0 to 1
Reasoning (Reasoning Controls)
reasoning_effortReasoning effort before answering.
string
"low", "medium", "high"
"low", "medium", "high"
"low", "medium", "high"
"low", "medium", "high"
Tool Use (Function Calls & Tools)
tool_choiceHow the model should use tools.
string
"auto", "required", "none"
"auto", "required", "none"
"auto", "required", "none"
"auto", "required", "none"
toolsTool/function definitions available to the model.
array
Output & Format (Response Formatting)
response_formatStructured output format configuration.
string
"text", "json_object"
-
-
-
Request Behaviour (Request Config)
streamStream partial responses as they are generated.
bool
true | false
true | false
true | false
true | false
Other
thinking
bool
true | false
true | false
true | false
true | false

Performance

Median throughput and time to first token per provider over the last week.

Throughput

Latency

Make your first API call

OpenAI-compatible. Point your SDK at FastRouter, or call the API directly.

Full API docs
Replace <FASTROUTER_API_KEY> with your key · Get your key →Install
OpenAI SDKHTTP
from openai import OpenAI
client = OpenAI(
base_url="https://api.fastrouter.ai/api/v1", # FastRouter base URL
api_key= "<FASTROUTER_API_KEY>", # Replace with your FastRouter API key
)
completion = client.chat.completions.create(
model="deepseek/deepseek-v4.1-flash-1017", # Replace with your model ID
messages=[
{ "role": "user", "content": "What is the meaning of life?" }
]
)
print(completion.choices[0].message.content)

Frequently asked questions

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Model scores sourced from ArtificialAnalysis