One-line summary
This is a follow-up/update: the site already covers the original V4.1 Flash launch, comparisons and pricing. On the afternoon of October 17, 2026, DeepSeek updated V4.1 Flash to V4.1-Flash-1017 across the official web app, mobile app and API, and simultaneously opened its in-house search API (Search and Fetch interfaces, both priced at CNY 5 per 1,000 calls).
Event Overview
On the afternoon of October 17, 2026, DeepSeek officially announced that V4.1 Flash had been updated to V4.1-Flash-1017, with the web app, mobile app and API models switched to the new version. V4.1 Flash was originally released by DeepSeek on September 10, 2026, so this update came just over one month later. DeepSeek described the release as "a minor update" focused on improvements in reasoning, coding, agent tasks and vision benchmarks, while also shortening task execution time and output length.
Key Information
| Item | Details |
|---|---|
| Publisher | DeepSeek |
| Announcement time | Afternoon of October 17, 2026 |
| New version | V4.1-Flash-1017 |
| Scope | Official web app, mobile app and API models switched |
| Search API | New Search and Fetch interfaces, both CNY 5 per 1,000 calls, opened to the public |
| Benchmarks | Top scores on DeepSWE v1.1, Automation-Bench, Agents' Last Exam and Apex Bench v1.1, ahead of Claude Opus 5, GPT-5.6 Sol, Kimi K3 and GLM 5.3 |
| Targeted optimization | DeepSeek Harness 0.2.1, Tencent CodeBuddy, WorkBuddy and other platforms |