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DeepSeek V4 Open Source Release: 1.6 Trillion Parameters, Million-Token Context Window

by ChaoBro
#DeepSeek #Open Source #Large Models #Context Window

In late April 2026, DeepSeek released open-source model V4, reaching 1.6 trillion parameters with support for up to 1 million token context windows. This is one of the largest-scale open-source models globally, matching top-tier closed-source systems in both parameter count and context capability.

Core Specifications

VersionFeaturesPrice
V4Full 1.6T parameter versionOpen source
V4-ProOptimized for production~$1,071 (AI Index evaluation cost)
V4-FlashLightweight high-speed version~1/166 of GPT-5.5 pricing

Impact on Open Source Ecosystem

  • Lower self-deployment barriers: Enterprises can run near-top-tier models on their own infrastructure
  • Reduced fine-tuning costs: Open weights enable vertical domain adaptation without training from scratch
  • Context window race: 1M token capability enables long document processing and codebase understanding

Comparison with Same-Week Competitors

ScenarioBest ChoiceKey Metric
Code generationClaude Opus 4.7SWE-Bench 87.6%
Complex reasoningGPT-5.5Terminal-Bench 82.7%
Cost-effectivenessDeepSeek V4-Flash1/166 of GPT-5.5 price
ScaleDeepSeek V41.6T parameters

Quick Start

pip install transformers
# Or use DeepSeek official SDK for API calls

Key Sources

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