Models / DeepSeek
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Reasoning

DeepSeek-V3.1

Advanced reasoning model with hybrid thinking capabilities

About model

Revolutionary Hybrid AI:
DeepSeek-V3.1 is a groundbreaking hybrid model that switches between thinking and non-thinking modes, delivering exceptional performance in reasoning, coding, and agent tasks. Built on a massive 671B parameter MoE architecture with 37B activated parameters, it offers unparalleled flexibility for developers seeking both fast responses and deep analytical capabilities.

Performance benchmarks

Model

FrontierMath Tier 4

GPQA Diamond

HLE

SciCode

GDPval-AA

Terminal-Bench 2.1

Agent Arena

FrontierCode

DeepSWE

74.9%

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  • Model card

    Architecture Overview:
    • Mixture-of-Experts (MoE) architecture with 671B total parameters and 37B activated parameters
    • Built upon DeepSeek-V3.1-Base with two-phase long context extension approach
    • Extended training with 630B tokens for 32K phase and 209B tokens for 128K phase
    • Compatible with UE8M0 FP8 scale data format for microscaling optimization

    Training Methodology:
    • Post-trained on expanded dataset with additional long documents
    • 10-fold increase in 32K extension phase training
    • 3.3x extension in 128K phase training
    • Advanced post-training optimization for tool usage and agent tasks

    Performance Characteristics:
    • Hybrid mode supporting both thinking and non-thinking operations
    • Superior performance on MMLU-Redux (91.8% non-thinking, 93.7% thinking)
    • Exceptional coding capabilities with LiveCodeBench Pass@1 of 56.4% (non-thinking) and 74.8% (thinking)
    • Advanced math reasoning with AIME 2024 Pass@1 of 66.3% (non-thinking) and 93.1% (thinking)

  • Applications & use cases

    Advanced Reasoning & Analysis:
    • Complex mathematical problem solving with step-by-step reasoning
    • Scientific research and analysis with transparent thought processes
    • Academic writing and research with comprehensive literature review capabilities
    • Strategic planning and decision-making with multi-factor analysis

    Software Development & Engineering:
    • Full-stack application development with multi-language support
    • Code review and optimization with detailed explanations
    • Architecture design and system planning
    • Debugging and troubleshooting with systematic approaches

    Agent & Automation Tasks:
    • Autonomous code agents for software development workflows
    • Search agents for information gathering and analysis
    • Multi-step task automation with tool integration
    • Workflow orchestration and process optimization

    Enterprise & Business Applications:
    • Data analysis and reporting with comprehensive insights
    • Technical documentation and knowledge management
    • Customer support and query resolution
    • Process automation and workflow optimization

Related models
  • Model provider
    DeepSeek
  • Type
    LLM
    Chat
    Reasoning
  • Main use cases
    Chat
  • Fine tuning
    Supported
  • Speed
    High
  • Intelligence
    Very High
  • Deployment
    Dedicated
  • Parameters
    671B
  • Activated parameters
    37B
  • Context length
    128K
  • Input modalities
    Text
  • Output modalities
    Text
  • Released
    August 20, 2025
  • Last updated
    August 26, 2025
  • Quantization level
    FP4
  • External link
  • Category
    Chat