NVIDIA: Nemotron 3 Ultra (free)✓ Catalog verified
NVIDIA Nemotron 3 Ultra is an open frontier-reasoning and orchestration model from NVIDIA, with 55B active parameters out of 550B total (MoE). Built on a hybrid Transformer-Mamba mixture-of-experts architecture, it...
Overview
NVIDIA Nemotron 3 Ultra is an open frontier-reasoning and orchestration model from NVIDIA, with 55B active parameters out of 550B total (MoE). Built on a hybrid Transformer-Mamba mixture-of-experts architecture, it...
Access: available through the official Nvidia API. Context window: 1M.
Specifications
| API identifier | nvidia/nemotron-3-ultra-550b-a55b:free |
| Provider | Nvidia |
| Model type | Text LLM |
| Context window | 1M catalog |
| Input modalities | text |
| Output modalities | text |
| Released | Jun 4, 2026 |
| Moderated | No |
| Architecture modality | text->text |
API defaults
{
"top_k": null,
"top_p": 0.95,
"temperature": 1,
"presence_penalty": null,
"frequency_penalty": null,
"repetition_penalty": null
}Pricing
Live pricing components for nvidia/nemotron-3-ultra-550b-a55b:free as published in the catalog.
| Pricing component | Raw unit price | Normalized | Unit |
|---|---|---|---|
| Prompt tokens | $0 | $0.00 / 1M | Per input token |
| Completion tokens | $0 | $0.00 / 1M | Per output token |
| Request fee | N/A | N/A | Per request |
| Image fee | N/A | N/A | Per image unit |
| Web search fee | N/A | N/A | Per search request |
Cost calculator
Estimate monthly spend from your own token volumes.
Estimated Total Cost
$0Calculated from current list pricing in the ModelsAtlas catalog.Capabilities
| Capability | Status | What it means |
|---|---|---|
| Visual Understanding | Not advertised | Image and document analysis support |
| Audio Processing | Not advertised | Speech and voice aligned flows |
| Tool Calling | ✓ Supported | Supports tools / function calling |
| Self-Hosting | Not advertised | Deploy outside managed APIs |
Capability signals
Directional signals derived from model metadata and capability tags — not official benchmark submissions.
Quick start
Call NVIDIA: Nemotron 3 Ultra (free) through an OpenAI-compatible client.
from openai import OpenAI
client = OpenAI(
base_url="https://openrouter.ai/api/v1",
api_key="YOUR_API_KEY"
)
response = client.chat.completions.create(
model="nvidia/nemotron-3-ultra-550b-a55b:free",
messages=[{"role": "user", "content": "Explain quantum physics."}]
)
print(response.choices[0].message.content)Alternatives
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| Anthropic Claude Sonnet Latest | ~anthropic | 1M | $2.00 | View → |
| Anthropic: Claude Fable Latest | ~anthropic | 1M | $10.00 | View → |
Sources & attribution
Pricing and metadata are maintained in the ModelsAtlas catalog.
Frequently asked questions
How much does NVIDIA: Nemotron 3 Ultra (free) cost?
$0.00 per 1M input tokens and $0.00 per 1M output tokens on the official Nvidia API.
What is the context window of NVIDIA: Nemotron 3 Ultra (free)?
NVIDIA: Nemotron 3 Ultra (free) supports up to 1M tokens of context.
Does NVIDIA: Nemotron 3 Ultra (free) support tool / function calling?
Yes, NVIDIA: Nemotron 3 Ultra (free) supports tool / function calling — you can register tools and the model will emit structured tool calls.
How do I access NVIDIA: Nemotron 3 Ultra (free)?
Use the official Nvidia API with the model id `nvidia/nemotron-3-ultra-550b-a55b:free`. See the Quick start section above for code examples.