Which is cheaper, Nemotron 3 Ultra 550B A55B and GPT-6.1 Sol?

Nemotron 3 Ultra 550B A55B has the lowest input price. Per 1M input tokens: Nemotron 3 Ultra 550B A55B from $0.50 and GPT-6.1 Sol from $2.00.

Which has the larger context window, Nemotron 3 Ultra 550B A55B and GPT-6.1 Sol?

GPT-6.1 Sol has the largest context window: Nemotron 3 Ultra 550B A55B 262,144 tokens and GPT-6.1 Sol 1,050,000 tokens.

Can I switch between Nemotron 3 Ultra 550B A55B and GPT-6.1 Sol without changing my code?

Yes. All of them are served through FastRouter's OpenAI-compatible API, so switching is a change of the model parameter (nvidia/nemotron-3-ultra-550b-a55b, openai/gpt-6.1-sol).

Nemotron 3 Ultra 550B A55B vs GPT-6.1 Sol

Side-by-side pricing per provider, context window, benchmark scores and speed, all on one OpenAI-compatible API.

Estimate monthly cost for these models

Nemotron 3 Ultra 550B A55B NVIDIAnvidia/nemotron-3-ultra-550b-a55b

GPT-6.1 Sol OpenAIopenai/gpt-6.1-sol

Creator

NVIDIA

OpenAI

Released

May 16, 2026

Sep 29, 2026

Context window

262K

1.05M

Max output

16K

128K

Input / 1MLowest provider price

$0.50

$2.00

Output / 1MLowest provider price

$2.20

$10.00

Providers

IntelligenceArtificial Analysis index

11.8

54.6

Accepts

Text

Text, Image, Files

Produces

Text

Tool calling

Yes

Structured output

Yes

Reasoning

Yes

Nemotron 3 Ultra 550B A55B vs GPT-6.1 Sol: summary

Nemotron 3 Ultra 550B A55B and GPT-6.1 Sol are both available through FastRouter's OpenAI-compatible API, so switching between them is a change of model id, not a new integration.

Nemotron 3 Ultra 550B A55B, from NVIDIA, has a 262,144-token context window, costs $0.50/1M input and $2.20/1M output tokens and scores 11.8 on the Artificial Analysis Intelligence Index.

GPT-6.1 Sol, from OpenAI, has a 1,050,000-token context window, costs $2.00/1M input and $10.00/1M output tokens and scores 54.6 on the Artificial Analysis Intelligence Index.

Nemotron 3 Ultra 550B A55B is the cheapest on input, 4× cheaper than the next model, GPT-6.1 Sol has the largest context window and GPT-6.1 Sol scores highest for intelligence.

Switch with one line

client = OpenAI(base_url="https://api.fastrouter.ai/api/v1", api_key="<FASTROUTER_API_KEY>") client.chat.completions.create(model="nvidia/nemotron-3-ultra-550b-a55b", messages=[...]) # or client.chat.completions.create(model="openai/gpt-6.1-sol", messages=[...])

Full API docs

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Benchmark scores sourced from ArtificialAnalysis