Meta: Llama 3.1 405B Instruct
Review
Meta's Llama 3.1 405B Instruct is a large open-weight model with a 131K context window, but no benchmark data is available for this variant; at $4/1M tokens it is not particularly cost-effective without verified performance data.
Assessment date: April 4, 2026
Our methodology takes into account a range of factors including pricing, functionality, capabilities, benchmark performance, and real-world applicability. Rankings are reviewed and updated regularly as new models are released. Issues with our rankings? Contact us
Performance Profile
The highly anticipated 400B class of Llama3 is here! Clocking in at 128k context with impressive eval scores, the Meta AI team continues to push the frontier of open-source LLMs. Meta's latest class of model (Llama 3.1) launched with a variety of sizes & flavors. This 405B instruct-tuned version is optimized for high quality dialogue usecases. It has demonstrated strong performance compared to leading closed-source models including GPT-4o and Claude 3.5 Sonnet in evaluations. Usage of this model is subject to Meta's Acceptable Use Policy.
Architecture
| Modality | Text → Text |
| Tokenizer | Llama3 |
| Instruct Type | llama3 |
| Parameters | 405B |
Model Information
Pricing
| Token Type | Cost per 1M tokens | Cost per 1K tokens |
|---|---|---|
| Input | $4.00 | $0.004000 |
| Output | $4.00 | $0.004000 |
