DeepSeek Announced Sep 10, 2026

DeepSeek V4.1 Flash

Available on MiniRouter for text generation. DeepSeek reports stronger coding results than V4 Flash.

Architecture
552B MoE
Causal Encoder–Decoder; 8B active input parameters, 16B output.
Model limits
1M context / 384K output
Text and image input. MiniRouter supports text only.
DeepSeek API ID
deepseek-flash
MiniRouter: deepseek/deepseek-v4.1-flash.
Weights
MIT license
Open weights and technical report.

Publisher pricing

Publisher-listed API price phases in US dollars per million tokens.
PhaseInput / 1MOutput / 1MBlended / 1MEffectiveSource
Off-peak$0.15$0.60$0.26Sep 10, 2026open-endedDeepSeek
Peak · weekdays 01–04 / 06–10 UTC$0.30$1.20$0.52Sep 10, 2026open-endedDeepSeek

Publisher-reported benchmarks

BenchmarkReported resultReported byAs ofSource
DeepSWE v1.174.2%DeepSeekSep 10, 2026Announcement ↗
Terminal Bench 2.190.6%DeepSeekSep 10, 2026Announcement ↗
Terminal Bench 3.030.0%DeepSeekSep 10, 2026Announcement ↗
Terminal Bench 4.031.2%DeepSeekSep 10, 2026Announcement ↗
GPQA Diamond90.9%DeepSeekSep 10, 2026Announcement ↗
CyberGym88.1%DeepSeekSep 10, 2026Announcement ↗
  • DeepSeek's API replaces V4 Flash and V4 Flash Vision Exp with V4.1 Flash. The deepseek-v4-pro alias switches on September 14 at 04:00 UTC.
  • Prices apply from September 10 at 04:00 UTC. Cached input: $0.003/M off-peak, $0.006/M peak. MiniRouter adds 5%.
  • GPQA Diamond: 90.9%, versus V4 Pro's 92.4% in DeepSeek's results.

Related coverage

Sources

  1. DeepSeek V4.1 Flash model card

    Published Sep 10, 2026

    Read at DeepSeek
  2. DeepSeek Models & Pricing

    Published Sep 10, 2026

    Read at DeepSeek