Meta AI Open Weights (Llama 3.1 Community License)Status: active

Llama 3.1 405B Instruct

Meta's largest open foundation model with 405 billion dense parameters, rivaling leading closed frontier models.

Released: Jul 23, 2024
Last Verified: Aug 10, 2026
Context Window

128k

Tokens

Max Output

8.192k

Output limit

Architecture

Dense Transformer

Model family

Parameters

405B

Total / Active

Input Token Cost

$1.79

Per 1M tokens

Output Token Cost

$1.79

Per 1M tokens

Model Overview

Llama 3.1 405B Instruct is the first openly available model of its scale, offering frontier-class knowledge, reasoning, and coding capabilities. Ideal for synthetic data generation and distilling smaller models.

Developer Implementation Notes

Requires an 8x H100 or 8x A100 GPU cluster (minimum ~230GB in FP8, 810GB in FP16) for self-hosting. Available on serverless cloud providers.

Key Strengths

  • Largest openly accessible foundation model in the world
  • Gold standard for synthetic data generation and teacher distillation
  • Exceptional multilingual understanding across 8+ languages

Limitations & Boundaries

  • Massive hardware requirements (8x 80GB GPUs minimum)
  • High cloud hosting cost compared to 70B MoE models

Capabilities & Modalities

Modalities:text
Reasoning Chains:No
Tool / Function Calling:Supported
Structured Outputs:Supported
Fine-Tuning:Supported
Local Deployment:Yes
Min VRAM:230 GB

Best Production Use Cases

  • Model distillation and synthetic dataset curation
  • Frontier research on open weights
  • Complex multilingual reasoning

Verified Benchmark Results

Standardized evaluations with methodology notes and authoritative citation links.

View all industry benchmarks →
Official benchmark results are currently being verified for this model release.

Pricing & Inference Cost Calculator

Token Cost Estimator – Llama 3.1 405B Instruct

Calculate projected inference spend with prompt caching

Quick Workload Presets

Input Tokens / Req2,000
100100k200k
Output Tokens / Req500
5016k32k
Number of Requests1,000
125k50k
Cache Hit Rate0%
0% (No cache)50%90% (Max)
Total Input Spend

$3.5800

2.00M input tokens

Total Output Spend

$0.8950

0.50M output tokens

Estimated Total Cost

$4.47

Avg: $0.00447 / req

Rates: $1.79 in / $1.79 out per million tokens (Together AI / Fireworks Cloud)Last verified: Aug 10, 2026

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Data Accuracy & Verification Notice

AI model specifications, pricing records, and benchmark metrics published on this platform are compiled directly from authoritative sources (official provider documentation, research papers, and verified evaluation harnesses). Benchmark results reflect specific test harnesses and prompting methodologies; scores are not directly comparable across differing evaluation setups.