NVIDIA Nemotron 3 Ultra 550B A55B API
Run nvidia/NVIDIA-Nemotron-3-Ultra-550B-A55B through FastInfra's API.
Pay per token on your FastInfra account — OpenAI-compatible chat API.
API access for nvidia/NVIDIA-Nemotron-3-Ultra-550B-A55B
One Base URL and API key for every model. Use the endpoint that matches the capability — not every model uses chat completions.
| Field | Value |
|---|---|
| Model ID | nvidia/NVIDIA-Nemotron-3-Ultra-550B-A55B |
| Capability | Chat |
| Base URL | https://api.fastinfra.ai/v1 |
| Primary endpoint | POST https://api.fastinfra.ai/v1/chat/completions |
| Auth | Authorization: Bearer YOUR_API_KEY |
| OpenAI Chat SDK | Yes — set base_url to the Base URL |
| Validate model id | GET https://api.fastinfra.ai/v1/models/nvidia/NVIDIA-Nemotron-3-Ultra-550B-A55B |
| Docs | Integration reference |
Point the OpenAI SDK at the Base URL above with your FastInfra API key.
NVIDIA Nemotron 3 Ultra 550B A55B pricing
Billed per token used on your FastInfra account.
| Direction | Price per 1M tokens |
|---|---|
| Input | $0.53 |
| Output | $2.31 |
1 route available
Requests route to route-21 by default (lowest cost). FastInfra fails over automatically if a route is unavailable.
| Route label | Model ID |
|---|---|
route-21 |
nvidia/NVIDIA-Nemotron-3-Ultra-550B-A55B |
Call NVIDIA Nemotron 3 Ultra 550B A55B in 30 seconds
Works with any OpenAI SDK — change the base URL and API key only.
Python
from openai import OpenAI
client = OpenAI(api_key="YOUR_API_KEY", base_url="https://api.fastinfra.ai/v1")
response = client.chat.completions.create(
model="nvidia/NVIDIA-Nemotron-3-Ultra-550B-A55B",
messages=[{"role": "user", "content": "Hello!"}]
)
print(response.choices[0].message.content)
curl
curl https://api.fastinfra.ai/v1/chat/completions \
-H "Authorization: Bearer YOUR_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"model": "nvidia/NVIDIA-Nemotron-3-Ultra-550B-A55B",
"messages": [{"role": "user", "content": "Hello!"}]
}'
NVIDIA Nemotron 3 Ultra 550B A55B — common questions
How much does the nvidia/NVIDIA-Nemotron-3-Ultra-550B-A55B API cost?
On FastInfra, nvidia/NVIDIA-Nemotron-3-Ultra-550B-A55B costs $0.525/1M input, $2.31/1M output tokens. Billing is per token used, with no subscription.
Is nvidia/NVIDIA-Nemotron-3-Ultra-550B-A55B compatible with the OpenAI SDK?
Yes. FastInfra exposes nvidia/NVIDIA-Nemotron-3-Ultra-550B-A55B through an OpenAI-compatible endpoint at https://api.fastinfra.ai/v1 — point any OpenAI SDK at that base URL with a FastInfra API key and keep your existing code.
How does routing work for nvidia/NVIDIA-Nemotron-3-Ultra-550B-A55B?
nvidia/NVIDIA-Nemotron-3-Ultra-550B-A55B is available on 1 route(s): route-21. Requests use route-21 by default (lowest cost). FastInfra fails over automatically if a route is unavailable.
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