In brief

  • What happened: on October 17, 2026, DeepSeek released DeepSeek-V4.1-Flash-1017. According to the company, it is an update to V4.1 Flash with stronger results, shorter outputs, and faster task completion.
  • How to use it: it is live on the website, app, and API. The API model name stays deepseek-flash. API prices did not change. The weights are on Hugging Face and ModelScope under the MIT license.
  • New platform tools: Search and Fetch are open to API users at $0.75 per 1,000 successful calls per endpoint.

DeepSeek kept the product name and swapped what sits behind it. According to the company, V4.1-Flash-1017 does more on agent and coding work while cutting output length and runtime.

AI Desk · Published October 17, 2026
First look: this report is based on DeepSeek’s official release notes, pricing page, and Hugging Face model card. Maitz has not run the model hands-on.

What shipped?

According to DeepSeek, V4.1-Flash-1017 is a minor update to DeepSeek-V4.1-Flash with substantial gains in reasoning, coding, agent tasks, and visual benchmarks. The company also reports shorter outputs and faster task completion. It describes the change as a Pareto improvement on the performance–cost curve.

The build is live on the website, the app, and the API. The API still uses the model name deepseek-flash. Legacy names such as deepseek-v4-flash are still accepted, but the docs say those models have been retired and requests are routed to 1017 at Flash pricing.

DeepSeek also highlights reinforcement learning with self-feedback for end-to-end project building. Official demos include a browser racing game, a Portal 2-style recreation in Godot, and 3D scenes. Those are company examples, not Maitz tests.

What do the company numbers say?

On the Hugging Face model card, DeepSeek publishes a comparison table against the previous Flash build and other models. These figures belong to the company. We did not re-run them.

Benchmark (per DeepSeek)V4.1-Flash-1017Prior V4.1-Flash
DeepSWE v1.177.074.2
Terminal-Bench 4.042.331.2
ProgramBench29.120.3
Automation-Bench v1.0.660.554.8
Apex Bench v1.172.164.6

The same table also lists GPT-5.6 Sol and Claude Opus 5. On DeepSWE, DeepSeek reports 77.0 versus 73.0 and 74.0. On Terminal-Bench 4.0 its score sits below Opus 5. Treat those as company claims, not an independent Maitz eval.

Price and access

According to the official pricing page, Flash rates did not change with 1017. Off-peak: $0.15 per million input tokens on a cache miss, $0.003 on a cache hit, and $0.6 per million output tokens. Peak rates are double. Context length is 1M tokens, and the listed maximum output is 384K.

The weights themselves are downloadable under MIT. For teams that self-host, that means the files can be used under MIT terms without a separate model commercial license. Exact local VRAM needs are not spelled out on the short card; the Hugging Face repo points to an inference folder.

Search and Fetch: live web access

On the same day, DeepSeek opened two tools to all API users. Search finds web pages for a query and returns structured results. Fetch pulls a single page and returns Markdown. According to the company, both run on its in-house search engine.

Price: $0.75 per 1,000 successful requests on each endpoint. Until October 31, 2026 at 16:00 UTC, Search and Fetch calls made through server-side tools in DeepSeek Harness, Claude Code, and Codex are free for DeepSeek API users. Billing starts after that.

What is still unknown

  • We have not tested the model in chat, via the API, or locally.
  • The benchmark table is DeepSeek’s. There is no independent Maitz reproduction here.
  • Comfortable local VRAM needs are still unclear from the short card.
  • Local latency and availability were not measured.

What it means for you

  • App and web users: if you already use DeepSeek, the company says you get 1017 without changing settings.
  • API developers: you can keep calling deepseek-flash. It is worth checking whether the same tasks cost less because outputs are shorter, and trying Search/Fetch before the end of October if you use Harness, Claude Code, or Codex.
  • Self-hosters: MIT weights are available. That fits the recent wave of open models, including NVIDIA’s Nemotron 3.5 Super VL.

Sources

  • DeepSeek API Docs: DeepSeek-V4.1-Flash-1017 Release, api-docs.deepseek.com/news/news261017/, October 17, 2026
  • DeepSeek: Models & Pricing, api-docs.deepseek.com/quick_start/pricing
  • DeepSeek: Search & Fetch guide, api-docs.deepseek.com/guides/search
  • Hugging Face: deepseek-ai/DeepSeek-V4.1-Flash-1017
  • Verified: October 17, 2026