AI Model Comparison

Llama 3.1 405B

Llama 3.1 405B — Meta large language model (2024) with a 128K-token context window and an MMLU score of 88.6%, released with open weights.

Key specifications

MMLU (capability)88.6%
Context window (K tokens)128
Input price ($/1M)0
Output price ($/1M)0

About Llama 3.1 405B

The Llama 3.1 405B is a large language model from Meta with a 128K-token context window and an MMLU score of 88.6%. It is open weights, so it can be self-hosted. MMLU measures general knowledge and reasoning; real-world quality also depends on coding, tool use, latency and safety.

The comparisons below show how Llama 3.1 405B stacks up against the alternatives people most often weigh against it, with the specific numbers laid out side by side.

Frequently asked questions

Is the Llama 3.1 405B any good?

Llama 3.1 405B — Meta large language model (2024) with a 128K-token context window and an MMLU score of 88.6%, released with open weights.

What are the key specs of the Llama 3.1 405B?

See the specification table above for the full breakdown.

MC
Marcus Chen
Hardware & Product Analyst

Marcus benchmarks processors, GPUs, phones and vehicles and maintains normalized performance databases.

MSc Computer Engineering10+ years review experience
✓ Reviewed by Priya Nair, Data Quality Reviewer.
Last updated 2026-05-01

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