LLM Perks

Nemotron 3 Ultra

Free right now Frontier
ReasoningCodingTool useLong contextOpen weights

Nemotron 3 Ultra is a language model with 550B parameters from NVIDIA. It is currently free at 3 providers with up to 1M tokens of context. The model supports step-by-step reasoning, is suited to coding, supports tool calling. Its weights are open, so it can also run locally.

Developer
NVIDIA
Parameters
550B / 55B active
Context
1M tokens
Type
Text
License
Open weights

Where to use Nemotron 3 Ultra for free

Each row is a separate free endpoint with its own limits.

ProviderContextLimitCard
OpenRouter
nvidia/nemotron-3-ultra-550b-a55b:free
1M Free tier No Open
NVIDIA Build
nvidia/nemotron-3-ultra-550b-a55b
1M Free serverless inference for development; limits and model availability may change. No Open
UnoRouter
nemotron-3-ultra-550b-a55b:free
1M No-card free models use shared capacity and per-model limits; availability can change. No Open

Quick start

curl https://openrouter.ai/api/v1/chat/completions \
  -H "Authorization: Bearer $OPENROUTER_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "nvidia/nemotron-3-ultra-550b-a55b:free",
    "messages": [{"role": "user", "content": "Hello!"}]
  }'

Example for OpenRouter. Any OpenAI-compatible client works: Cursor, Cline, OpenCode, Open WebUI.

Benchmarks

Intelligence Index
22.9
GPQA Diamond
86.7%
Humanity's Last Exam
28.4%
Terminal-Bench Hard
36.4%
τ²-Bench
83.3%
Long context (LCR)
79.3%

Source: Artificial Analysis · Nemotron 3 Ultra 550B A55B (Reasoning)

Similar free models

FAQ

Is Nemotron 3 Ultra free?

Yes. As of September 26, 2026, Nemotron 3 Ultra is free at OpenRouter, NVIDIA Build, UnoRouter. Each provider has its own limits — see the table above.

What is the context window of Nemotron 3 Ultra?

The largest context among free routes is 1,048,576 tokens. Some providers cap it lower.

How do I call Nemotron 3 Ultra via API?

Use any OpenAI-compatible client with base URL https://openrouter.ai/api/v1, model ID nvidia/nemotron-3-ultra-550b-a55b:free, and a OpenRouter key.

How good is Nemotron 3 Ultra?

Artificial Analysis Intelligence Index: 22.9, GPQA Diamond: 87%. For comparison, the strongest free model in the catalog right now is GLM 5.3.

Is Nemotron 3 Ultra open-weight?

Yes, the weights are published — you can download and run it locally, for example with Ollama or LM Studio.