AI Model Profile · Meta AI
Llama 3.1-405B
Llama 3.1-405B is an AI model developed by Meta AI (United States), released July 23, 2024. It has approximately 405B parameters. It was trained on about 3.8×1025 FLOP of compute. Its weights are openly released.
Frontier model · Open weights · Epoch confidence: Confident · Source: Epoch AI · Updated 2026-08-17
Specifications
| Developer | Meta AI |
| Country | United States |
| Released | July 23, 2024 |
| Domain | Language |
| Parameters | 405B |
| Training compute | 3.8×1025 FLOP |
| Training cost (2023 USD) | $53m |
| Training hardware | 16,384× NVIDIA H100 SXM5 80GB |
| Training power draw | 22.6 MW |
| Weights | Open |
| Access | Open weights (restricted use) |
| Frontier model | Yes |
All figures from Epoch AI's Notable AI Models database (CC BY 4.0). Blank fields are undisclosed by the developer — never estimated by Affärslivet.
Benchmarks
Performance on Epoch AI's reproducible evaluations (higher is better; scores are the best across scorers). These are independent runs, not developer-reported numbers.
Source: Epoch AI Benchmarking Hub. GPQA Diamond = graduate-level science Q&A; SWE-Bench Verified = real software-engineering tasks; FrontierMath = research-level maths; MATH Level 5 = hardest competition maths; AIME = olympiad maths; SimpleQA = factual accuracy.
Frequently asked
- Who developed Llama 3.1-405B?
- Llama 3.1-405B was developed by Meta AI (United States) and released on July 23, 2024.
- How big is Llama 3.1-405B?
- Llama 3.1-405B has approximately 405B parameters and was trained on about 3.8×10^25 FLOP of compute, at an estimated training-compute cost of $53m. Source: Epoch AI.
- Is Llama 3.1-405B open source?
- Llama 3.1-405B is released with open weights (Yes), meaning its trained parameters are publicly available.
- How does Llama 3.1-405B perform on benchmarks?
- On Epoch AI's evaluations, Llama 3.1-405B scores 9.7% on AIME (OTIS Mock), 50.9% on GPQA Diamond, 49.8% on MATH Level 5. Source: Epoch AI Benchmarking Hub.
Sources
Cite this model profile
Free to cite, quote and reference under CC BY 4.0 — with attribution to Affärslivet. Writing an article or answer? Reference this model profile as:
APA
Affärslivet Research. (2026). Llama 3.1-405B — specifications & benchmarks. Affärslivet. https://xn--affrslivet-s5a.com/en/ai/models/llama-3-1-405b
MLA
"Llama 3.1-405B — specifications & benchmarks." Affärslivet, 2026-08-17, xn--affrslivet-s5a.com/en/ai/models/llama-3-1-405b.
Source: Affärslivet — xn--affrslivet-s5a.com/en/ai/models/llama-3-1-405b. Attribute to Affärslivet when citing or linking.