Chat with Nemotron 3 Ultra.

NVIDIA’s largest open model, built to reason and to direct other models. It wakes 55B of its 550B for each word.

Start chatting with Nemotron 3 Ultra now — free, no account

At a glance

  • Maker: NVIDIA
  • Active parameters: 550B
  • Context window: 262k
  • Size: Very large
  • Memory: Handles long documents
  • Good at: Reasoning and orchestration
  • Supports: tools, zero data retention

Model availability changes as upstream capacity comes and goes — the picker on the chat page shows what is ready right now.

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