Llama 3.1 405B
Llama 3.1 405B is a released coding, long context, and classification model with open-weight and 128k context; evaluate it while provider pricing coverage matures.
Use it for
- Teams evaluating coding, long context, and classification
- Workloads that can use a 128k context window
Do not use it for
- Cost-sensitive launches that need sourced token pricing
- Vision or document-understanding workloads
- Strict JSON or tool-calling flows
- Family
- Llama 3.1
- Released
- 2024-07-23
- Context
- 128k
- Parameters
- 405B
- Architecture
- Decoder Only
- Knowledge cutoff
- 2023-12
- Specialization
- general
- Openness
- Open weights
- License
- Llama 3 CommunityCommercial use: conditional
- Weights
- Available
- Code
- Unknown
- Training
- Fine-tuned
Large-scale open-source AI for social technologies.
No tracked provider token pricing is available yet.
About
The Llama 3.1 405B model is a cutting-edge large language model released by Meta on July 23, 2024. Boasting 405 billion parameters, it utilizes an optimized transformer architecture with Grouped-Query Attention (GQA) for improved inference scalability. The model supports eight languages and is fine-tuned using supervised fine-tuning (SFT) and reinforcement learning with human feedback (RLHF). Trained on approximately 15 trillion tokens with a knowledge cutoff in December 2023, it's designed for commercial and research applications, particularly in assistant-like chat scenarios. The model is available under a Community License, allowing for responsible use and modification .
Llama 3.1 405B is an open-weight model in the Llama 3.1 family. The structured metadata tracks a 128k-token context window. Headline tracked benchmarks include HellaSwag 95.8, HumanEval 89.0, and Massive Multitask Language Understanding 88.6.
Top use-case fit: coding, agents, and build tasks
Coding
1 relevant benchmark in the decision map.
Long context
Included by capability and metadata signals in the decision map.
Classification
2 relevant benchmarks in the decision map.
Provider price ladder
No tracked provider token pricing is available for this model yet.
Capabilities
No model capability flags are currently sourced.
Benchmark peer barsfor Coding
Benchmark scores(7)
| Benchmark | Score | Version | Source |
|---|---|---|---|
| HellaSwag | 95.8 | 10-shot | https://ai.meta.com/blog/meta-llama-3-1/ |
| HumanEval | 89.0 | pass@1 | https://ai.meta.com/blog/meta-llama-3-1/ |
| Massive Multitask Language Understanding | 88.6 | 5-shot | https://huggingface.co/spaces/open-llm-leaderboard/open_llm_leaderboard |
| Chatbot Arena | 1228.0 | — | https://lmarena.ai |
| Google-Proof Q&A | 51.5 | diamond | https://artificialanalysis.ai/leaderboards/models |
| Grade School Math 8K | 95.7 | — | https://ai.meta.com/blog/meta-llama-3-1/ |
| Mostly Basic Programming Problems+ | 77.5 | — | https://evalplus.github.io/leaderboard.html |
Migration checks
No linked migration route is available for this model yet.
Rankings & picks(1)
Compare Llama 3.1 405B with other models
Comparison and alternatives
Browse all comparisons →Show all 12 popular comparisonssorted by 7-day search impressions
Frequently asked questions
What is the context window of Llama 3.1 405B?
Llama 3.1 405B has a context window of 128k tokens.
When was Llama 3.1 405B released?
Llama 3.1 405B was released on 2024-07-23.
What benchmarks has Llama 3.1 405B been tested on?
Llama 3.1 405B has been evaluated on 7 benchmarks, including HellaSwag, HumanEval, Massive Multitask Language Understanding, Chatbot Arena, Google-Proof Q&A.
Large-scale open-source AI for social technologies.
No tracked provider token pricing is available yet.