Llama 3.1 405B Instruct
Llama 3.1 405B Instruct is Meta's flagship open-weights model, sitting at the top of the Llama 3.1 family released in July 2024. At 405 billion parameters, it matches or exceeds several leading proprietary models on complex reasoning, coding, and long-context tasks. Meta trained it on a massive multilingual corpus and aligned it for instruction following, making it one of the most capable openly available models for frontier applications.
The 405B Instruct variant is designed for organizations that require top-tier language understanding without ceding control of their data or model weights. Its 128K context window supports rich multi-document workflows, while its scale enables nuanced analysis, complex instruction adherence, and high-quality generation that smaller open models struggle to match. It is typically served on multi-GPU infrastructure or via API endpoints offered by cloud providers.
Key Features
Frontier-class reasoning and instruction following at open-weights scale
128K-token context window enabling deep multi-document analysis
High-quality multilingual generation across dozens of languages
Strong performance on complex coding and algorithmic problem solving
Open weights enabling private fine-tuning and on-premises deployment
Tool use and function calling for agentic and pipeline integrations
Ideal Use Cases
Complex research synthesis requiring nuanced multi-step reasoning
High-stakes legal, medical, or financial document analysis
Coding assistance on large, interrelated codebases
Building proprietary foundation model derivatives via fine-tuning
Enterprise AI pipelines requiring data residency compliance
Example Prompts for Llama 3.1 405B Instruct
Technical Specifications
| Provider | Meta |
| Category | Text |
| Modality | Text -> Text |
| Context Window | 128K tokens |
Frequently Asked Questions
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