Reason through complex work
Work through multi-step problems, compare possible solutions, and explain the reasoning behind an answer. Switch thinking on for harder tasks or off for a direct response.
REASONING · CODING · VISUAL UNDERSTANDING
DeepSeek-V4.1-Flash-1017
A multimodal AI model built for complex reasoning, coding, and agent workflows, with an architecture designed to reduce inference costs.
Debug a function, compare documents, or extract structured data. Use the playground to explore DeepSeek V4.1 Flash 1017, then bring the same text-chat API into your application.
Text chat with optional thinking.
MODEL / 1017DeepSeek-V4.1-Flash-1017
Reasoning and coding, with optional thinking.
- Upstream context
- 1M tokens
- Model input
- Text + images
- Thinking
- Optional
- This site’s API
- Text chat
MODEL CAPABILITIES
Reason, code, and understand images.
From short answers to multi-step tasks, choose the approach that suits the job.
Build with code
Find bugs, explore implementations, and write tests. DeepSeek reports stronger coding and agent benchmark results with the 1017 update.
Understand text and images
The model can interpret charts, screenshots, and other images. Our playground and API accept text; image input is available through the upstream model, not this service.
Work with more context
The model supports a 1M-token context window and up to 384K output tokens. Our API has smaller request limits, detailed in the API guide.
Model specifications: DeepSeek API documentation. Service limits: our API documentation.
BUILT FOR EFFICIENCY
Designed to do more with less compute.
V4.1 Flash uses a 552B-parameter mixture-of-experts architecture, activating 8B parameters for input and 16B for output. This asymmetric design is intended to reduce inference costs.
DeepSeek also reports smaller KV-cache storage requirements than the previous generation: one-quarter of the HBM and one-eighth of the SSD capacity. This reduces storage requirements for workloads that reuse context.
Architecture and storage figures: DeepSeek’s September release. These are model-level properties, not a promise of this service’s price or latency.
THE OCTOBER 17 UPDATE
What changed in DeepSeek V4.1 Flash 1017?
DeepSeek reports gains in reasoning, coding, agent tasks, and visual understanding, along with shorter runtimes and fewer output tokens in its evaluations.
Terminal-Bench 4.0
Claude Code framework
DeepSWE v1.1
Mini-SWE-V2 framework
Chartography
With tools
Scores reported by DeepSeek for the 1017 release. These measure the model under the listed evaluation setups, not this API service. Read the evaluation context.
PUT IT TO WORK
Try it on your everyday work.
Use these prompts as starting points for DeepSeek V4.1 Flash 1017. Add your own code or documents, then review the answer.
Development
Find the bug. Test the fix.
Review this function. Identify a failing input, propose a minimal fix, and write a regression test.
Review suggested code and run its tests.
View playground →Document analysis
Compare proposals without losing the details.
Compare these two proposals. Summarize the differences, cite supporting sections, and list unresolved questions.
Supply the relevant text and verify citations.
View playground →Data workflows
Extract the fields your app needs.
Extract tasks as JSON with title, owner, and due_date. Use null when a field is missing.
Validate the JSON and its values in your application.
View playground →BUILD WITH OUR API
Connect your app.
Track every request.
Create an API key, choose your credit source, and send a text-chat request. Your account keeps your balance, token usage, and request history in one place.
Create your API key
Create a key in your account and keep it on your server.
Choose your credits
Choose a $10–$200 credit pack at the same token rates, or claim the 20K-token trial when it is available in your account. Trial tokens last seven days.
Connect and track usage
Send text chat requests to our endpoint and review token usage and charges in your workspace.
Text chat, non-streaming: up to 32,000 input characters and 8,192 output tokens per request.
BEFORE YOU START
Frequently asked questions
What is DeepSeek V4.1 Flash 1017?
DeepSeek V4.1 Flash 1017 is the October 17, 2026 update to the V4.1 Flash model. It improves on the September release across reasoning, coding, agent, and visual evaluations reported by DeepSeek. API requests use deepseek-flash, an alias that may change with future model updates.
Can I buy API credits on this website?
Credit packs start at $10, with $20 and $50–$200 options. All packs use the same token rates and add to your USD balance. Manage purchases, API keys, and usage in your account. Check the pricing page for checkout availability.
Does this API include every upstream feature?
Our API supports text chat with optional thinking: up to 32 messages, 32,000 total input characters, and 8,192 output tokens per request. It does not accept images, tool calls, or streaming requests.
Is there a free trial?
The trial allowance is 20,000 tokens, valid for seven days after you claim it. Both input and output count toward the total, including cached input. Check your verified account for availability. Trial requests never use paid credit automatically.
GET STARTED
See what it can do for your project.
Choose a prompt in the playground or follow the API quickstart.