NVIDIA: Llama 3.1 Nemotron Ultra 253B v1

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

Created Apr 8, 2025131,072 context

$0.60/M input tokens$1.80/M output tokens

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 Recommendations for more.

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Total usage per day on OpenRouter

Prompt

344M

Completion

2.73M

Reasoning

Prompt tokens measure input size. Reasoning tokens show internal thinking before a response. Completion tokens reflect total output length.

Uptime stats for Llama 3.1 Nemotron Ultra 253B v1

Uptime stats for Llama 3.1 Nemotron Ultra 253B v1 across all providers

Sample code and API for Llama 3.1 Nemotron Ultra 253B v1

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