Llama 3.1 405BvsLlama 3 70B
Meta AI vs Meta AI — Side-by-side model comparison
Head-to-Head Comparison
| Metric | Llama 3.1 405B | Llama 3 70B |
|---|---|---|
| Provider | ||
| Arena Rank | #9 | — |
| Context Window | 128K | 8K |
| Input Pricing | Free (open)/1M tokens | Free (open)/1M tokens |
| Output Pricing | Free (open)/1M tokens | Free (open)/1M tokens |
| Parameters | 405B | 70B |
| Open Source | Yes | Yes |
| Best For | Complex reasoning, coding, multilingual tasks | General tasks, fine-tuning, instruction following |
| Release Date | Jul 23, 2024 | Apr 18, 2024 |
Llama 3.1 405B
Llama 3.1 405B is Meta's largest and most capable open-source language model, representing a major milestone as the first open model to rival top proprietary systems like GPT-4 and Claude 3.5 Sonnet across many benchmarks. With 405 billion parameters and a 128K context window, it excels at complex reasoning, coding, multilingual translation, and tool use. Its open-weight nature has made it a foundation for the open-source AI ecosystem, enabling organizations to deploy frontier-level AI without vendor lock-in.
View Meta AI profile →Llama 3 70B
Llama 3 70B was Meta's flagship open model at launch, significantly outperforming Llama 2 across all benchmarks with improved reasoning, coding, and instruction-following capabilities. It became one of the most downloaded and fine-tuned open models in history, spawning thousands of community variants and establishing Meta's position as the leader in open-source AI development.
View Meta AI profile →Key Differences: Llama 3.1 405B vs Llama 3 70B
Llama 3.1 405B supports a larger context window (128K), allowing it to process longer documents in a single request.
Llama 3.1 405B has 405B parameters vs Llama 3 70B's 70B, which affects inference speed and capability.
When to use Llama 3.1 405B
- +You need to process long documents (128K context)
- +Your use case involves complex reasoning, coding, multilingual tasks
When to use Llama 3 70B
- +Your use case involves general tasks, fine-tuning, instruction following
The Verdict
Llama 3.1 405B wins our head-to-head comparison with 3 out of 5 category wins. It's the stronger choice for complex reasoning, coding, multilingual tasks, though Llama 3 70B holds an edge in general tasks, fine-tuning, instruction following.
Last compared: March 2026 · Data sourced from public benchmarks and official pricing pages