OpenAI compatible API · Attested · Public status

NVIDIA: Nemotron 3 Ultra vs OpenAI: GPT-5.5

Compare NVIDIA: Nemotron 3 Ultra and OpenAI: GPT-5.5 by providers, context, price, and TrustedRouter route support.

Verify gateway

Onebase URL to migrate

100sof models and routes

Noneprompt logs by default

Compare routesProviders, price, context, and policy posture in one view.

Use auto when uptime mattersKeep a primary model and let fallback handle provider failures.

Same API shapeUse the OpenAI client and set the model you want.

Practical read

NVIDIA: Nemotron 3 Ultra has the lower cheapest prompt+completion route on TrustedRouter. NVIDIA: Nemotron 3 Ultra has more provider fallback routes, while OpenAI: GPT-5.5 has the larger context window. Probe-backed speed data is shown when enough recent samples exist.

$3.15/1MNVIDIA: Nemotron 3 Ultra cheapest route

$36.75/1MOpenAI: GPT-5.5 cheapest route

2713 msNVIDIA: Nemotron 3 Ultra measured p50 TTFT

not enough dataOpenAI: GPT-5.5 measured p50 TTFT

NVIDIA: Nemotron 3 UltraOpenAI: GPT-5.5

Model idnvidia/nemotron-3-ultra-550b-a55bopenai/gpt-5.5

PublisherTogetherOpenAI

AI IQ — IQ 132#3

Context512,288 tokens1,050,000 tokens

Provider routes74

Cheapest route$3.15/1M$36.75/1M

Privacy posturehas ZDR routeprovider posture varies

Modes chat chat

NVIDIA: Nemotron 3 Ultra routes

Overview7 endpoints
PricingPrompt and completion rates
ProvidersAll serving providers

OpenAI: GPT-5.5 routes

Overview4 endpoints
PricingPrompt and completion rates
BenchmarksTrustedRouter and external sources
ProvidersAll serving providers

Production choice

Pick a default model. Keep fallback enabled.

TrustedRouter is useful when you know the model you want, but still need provider rollover, budget limits, usage records, and a prompt path you can verify.

OpenAI clientPython

client = OpenAI(
    base_url="https://api.trustedrouter.com/v1",
    api_key="sk-tr-v1-..."
)

response = client.chat.completions.create(
    model="nvidia/nemotron-3-ultra-550b-a55b",
    messages=messages,
)