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NVIDIA: Llama 3.1 Nemotron Ultra 253B v1

nvidia/llama-3.1-nemotron-ultra-253b-v1

Model weights

Llama-3.1-Nemotron-Ultra-253B-v1 is a large language model (LLM) optimized for advanced reasoning, human-interactive chat, retrieval-augmented generation (RAG), and tool-calling tasks. Derived from Meta’s Llama-3.1-405B-Instruct, it has been significantly customized using Neural Architecture Search (NAS), resulting in enhanced efficiency, reduced memory usage, and improved inference latency. The model supports a context length of up to 128K tokens and can operate efficiently on an 8x NVIDIA H100 node.

Note: you must include detailed thinking on in the system prompt to enable reasoning. Please see Usage RecommendationsOpens in new tab for more.

Modalities
Context
131K
Released
Apr 8, 2025
Knowledge Cutoff
Mar 2024
ActivityFAQExplore

Activity

Token volume and request traffic to this model over time.

Not currently available through EU in-region routing. In-region routing docs

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Frequently asked questions

Llama-3.1-Nemotron-Ultra-253B-v1 is a large language model (LLM) optimized for advanced reasoning, human-interactive chat, retrieval-augmented generation (RAG), and tool-calling tasks. Derived from Meta’s Llama-3.1-405B-Instruct, it has been significantly customized using Neural Architecture Search (NAS), resulting in enhanced efficiency, reduced memory usage, and improved inference latency.

Llama 3.1 Nemotron Ultra 253B v1 has a 131,072 token context window.

Nemotron 3.5 Super VL, Nemotron 3.5 Lightning, Nemotron 3.5 Content Safety and 4 more are other text models from Nvidia.

Llama 3.1 Nemotron Ultra 253B v1 was released on April 8, 2025. Its knowledge cutoff is March 31, 2024.