NVIDIA: Nemotron 3 Ultra (free) — Free AI Model & API

Verified
openrouter/nvidia-nemotron-3-ultra-550b-a55b
chat reasoning
Get API key →
Context Window 1.0M
Max Output 66K
Released Invalid Date
Rate Limit See provider page
Cost $0.00 FREE
Free Period Since Jun 4, 2026
Credit Card Not required
Phone Verification Required
Status Online

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 supports text input and output with a context window of up to 1M tokens. It is suited for long-running agentic workflows, including agent orchestration, coding agents, deep research, and complex enterprise tasks. It is particularly strong at multi-step reasoning and planning, with high-throughput inference designed for high-volume agent pipelines. It is part of the NVIDIA Nemotron family of open models for agentic AI.

Model ID
nvidia/nemotron-3-ultra-550b-a55b:free
Base URL
https://openrouter.ai/api/v1
Specifications
Context: 1.0M · Output: 66K · Modality: text · OpenAI Compat: Yes ·Released: Jun 4, 2026

Quick Start

Integrate NVIDIA: Nemotron 3 Ultra (free) with 3 lines of code. See the config generator for Claude Code, Cursor, and more.

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": "Hello!"}]
)
print(response.choices[0].message.content)
import OpenAI from "openai";

const openai = new OpenAI({
  baseURL: "https://openrouter.ai/api/v1",
  apiKey: "YOUR_API_KEY",
});

const completion = await openai.chat.completions.create({
  model: "nvidia/nemotron-3-ultra-550b-a55b:free",
  messages: [{ role: "user", content: "Hello!" }],
});

console.log(completion.choices[0].message.content);
curl https://openrouter.ai/api/v1/chat/completions \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -d '{
    "model": "nvidia/nemotron-3-ultra-550b-a55b:free",
    "messages": [{"role": "user", "content": "Hello!"}]
  }'

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NVIDIA: Nemotron 3 Nano Omni (free)

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Rate Limits & Constraints

Rate Limit See provider page
Context Window 1.0M
Max Output Tokens 66K
Cost Free — since Jun 4, 2026
Credit Card Not required
OpenAI Compatible Yes — drop-in replacement

OpenRouter Platform Limitations

  • 200 RPD on free tier (1,000 with $10 lifetime credit)
  • Free models may change without notice
  • Some free models have shorter context windows than paid variants

Features & Use Cases

Best For

ChatReasoning

Modality Support

text

OpenRouter Highlights

  • 35+ permanently free models
  • OpenAI-compatible endpoint
  • 200 RPD free, 1,000 RPD with $10 lifetime credit
  • One key for 300+ models

How to Get a Free OpenRouter API Key

Follow these steps to get your free API key for NVIDIA: Nemotron 3 Ultra (free). No credit card required — just sign up and start using the API.

  1. Sign up at openrouter.ai No credit card. $10 lifetime top-up for 5× more rate limits.
  2. Go to Keys page
  3. Create a new API key
  4. Find free models Look for :free suffix in model name, or browse our list below.
  5. Configure OpenAI client Base URL: https://openrouter.ai/api/v1
Get your free API key → Learn more about OpenRouter

Playground — Test NVIDIA: Nemotron 3 Ultra (free)

Test NVIDIA: Nemotron 3 Ultra (free) directly in your browser. Your API key is sent directly to OpenRouter — never stored.

Model: NVIDIA: Nemotron 3 Ultra (free) Get Key

🔒 Your key is never stored — sent directly to the model provider via our server proxy.

Ready to chat with NVIDIA: Nemotron 3 Ultra (free).

Frequently Asked Questions

How do I get an API key for NVIDIA: Nemotron 3 Ultra (free)?

Sign up at OpenRouter to get your API key. No credit card is required — just an email sign-up. Once you have the key, use the code snippets in the Quick Start section above.

Is NVIDIA: Nemotron 3 Ultra (free) really free?

Yes. NVIDIA: Nemotron 3 Ultra (free) is available on OpenRouter's free tier and has been free since Jun 4, 2026. Rate limits apply: See provider page. Always check the provider's terms for any changes to the free tier.

What are NVIDIA: Nemotron 3 Ultra (free)'s rate limits?

See provider page Context window: 1.0M. Max output: 66K. No credit card required.

What are the best free alternatives to NVIDIA: Nemotron 3 Ultra (free)?

Popular free alternatives include Nex AGI: Nex-N2-Pro (free), NVIDIA: Nemotron 3.5 Content Safety (free), MiniMax: MiniMax M3. You can also browse all 169+ free models on our site.

More questions? See our full FAQ →

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