Open-weight LLM comparison
Llama 3.1 405B vs Llama 3.1 70B
Side-by-side
Straight from each model's release page and Hugging Face card. Memory shown is for the weights alone: add roughly 15% for real serving. Bold column marks the more parameters and the smaller memory footprint.
| Field | Llama 3.1 405B | Llama 3.1 70B |
|---|---|---|
| Total parameters | 405 B | 70 B |
| Architecture | dense | dense |
| Vendor | Meta | Meta |
| License | Llama 3.1 Community License | Llama 3.1 Community License |
| Released | 2024-07-23 | 2024-07-23 |
| Weights @ FP16 | 810 GB | 140 GB |
| Weights @ INT8 | 405 GB | 70 GB |
| Weights @ INT4 | 203 GB | 35 GB |
Which is smarter (published benchmarks)
Vendor-reported quality scores on the standard leaderboards. Bold column marks the higher score on the same test.
| Benchmark | Llama 3.1 405B | Llama 3.1 70B |
|---|---|---|
| MMLU (5-shot) | 88.6 | 86.0 |
| HumanEval | 89.0 | 80.5 |
| MATH (0-shot) | 73.8 | 68.0 |
| GPQA | 51.1 | 46.7 |
Sources: Llama 3.1 405B model card · Llama 3.1 70B model card. Benchmark methodology and prompt template can shift these numbers by several points, so treat these as relative rankings, not absolute scores.
Common questions
Llama 3.1 405B vs Llama 3.1 70B: which is bigger?
Llama 3.1 405B has more parameters (Llama 3.1 405B: 405 B; Llama 3.1 70B: 70 B). More parameters usually means higher ceiling on capability and higher memory requirement, though MoE architectures decouple total parameters from per-token compute.
Llama 3.1 405B vs Llama 3.1 70B: which needs less memory to serve?
Llama 3.1 70B needs less HBM. Weights-only footprint at FP16: Llama 3.1 405B 810 GB; Llama 3.1 70B 140 GB. Half those numbers at INT8, quarter at INT4. Real serving adds 10-30% for KV cache.
Llama 3.1 405B vs Llama 3.1 70B: which license is more permissive?
Llama 3.1 405B: Llama 3.1 Community License. Llama 3.1 70B: Llama 3.1 Community License. Apache 2.0 and MIT allow unrestricted commercial use; Llama Community License allows commercial use but restricts training larger models on outputs; CC-BY-NC and vendor-specific licenses (Qwen 72B, Gemma) have narrower terms. Check the model card for the exact clauses.
See also: every LLM comparison · Llama 3.1 405B full page · Llama 3.1 70B full page.