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Comparison · 2 models · Updated Oct 4, 2026

Nemotron 3 Ultra 550B A55B vs GPT-5.4 nano

GPT-5.4 nano comes out ahead, 68 to 62 on our weighted score, and it is the cheaper option too.

  1. NVIDIA

    Nemotron 3 Ultra 550B A55B

    Released Jun 4, 2026

    62/100
    • ECI146.2
    • Price$0.50 / $2.50
    • Context1M
    Full specs Remove Nemotron 3 Ultra 550B A55B
  2. Our pick

    OpenAI

    GPT-5.4 nano

    Released Mar 17, 2026

    68/100
    • ECI145.8
    • Price$0.20 / $1.25
    • Context400K
    Full specs Remove GPT-5.4 nano

  3. Add a model

    Make it a three-way comparison.

01 — Verdict

GPT-5.4 nano is our pick

GPT-5.4 nano is the better all-round choice, scoring 68/100 against Nemotron 3 Ultra 550B A55B (62). It leads on price and inputs & features. Nemotron 3 Ultra 550B A55B wins on context window. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.

  • CapabilityNemotron 3 Ultra 550B A55BCapabilities Index (ECI): Nemotron 3 Ultra 550B A55B 146.2 · GPT-5.4 nano 145.8
  • Lowest priceGPT-5.4 nanoGPT-5.4 nano $0.463 · Nemotron 3 Ultra 550B A55B $1.00 per 1M tokens (3:1 blend)
  • Longest contextNemotron 3 Ultra 550B A55BNemotron 3 Ultra 550B A55B 1,000,000 · GPT-5.4 nano 400,000 tokens
  • Widest inputsGPT-5.4 nanoNemotron 3 Ultra 550B A55B: Text · GPT-5.4 nano: Text, Images
  • Self-hostingNemotron 3 Ultra 550B A55BPublishes downloadable weights
How the score is built
MeasureWeightNemotron 3 Ultra 550B A55BGPT-5.4 nano
CapabilityCapabilities Index (ECI)50%7373
Price25%5066
Inputs & features15%4570
Context window10%6044
Overall100%62/10068/100
02 — Side by side

Every spec in one table

Highlighted cells lead their row. Dashes mean the data is not published.

Nemotron 3 Ultra 550B A55B vs GPT-5.4 nano specifications side by side
SpecificationNemotron 3 Ultra 550B A55BNVIDIAGPT-5.4 nanoOpenAI
Capability
Capabilities Index (ECI)146.2 (best)145.8
ECI rank#70 of 148 (best)#75 of 148
GPQA DiamondGraduate-level science questions85.4% (best)78.5%
FrontierMath Tiers 1–3Research-level mathematics—44.9%
OTIS Mock AIME 2024–2025Competition mathematics86.7%87.8% (best)
SimpleQA VerifiedShort factual questions—11.7%
Price per million tokens
Input$0.50$0.20 (best)
Output$2.50$1.25 (best)
Cached input$0.15$0.02 (best)
Blended (3:1)$1.00$0.463 (best)
Long-context rateSame rateSame rate
Price sourceOfficial Nvidia APIOfficial OpenAI API
Limits
Context window1,000,000 tokens (best)400,000 tokens
Max output128,000 tokens128,000 tokens
Inputs and features
TextYesYes
ImagesNoYes
PDFsNoNo
AudioNoNo
VideoNoNo
ReasoningYesYeslow · medium · high · xhigh
Tool callingYesYes
Structured outputYesYes
Availability
WeightsOpenProprietary
API model IDnvidia/nemotron-3-ultra-550b-a55bgpt-5.4-nano
API providers2126 (best)
ReleasedJun 4, 2026Mar 17, 2026
Knowledge cutoff—Aug 31, 2025
03 — Cost

What would a month cost?

Enter your expected volume in millions of tokens. List prices only; caching and batch discounts would lower these.

  • Nemotron 3 Ultra 550B A55B$10.00
  • GPT-5.4 nano$4.50
04 — Questions

Which should you choose?

Which is better: Nemotron 3 Ultra 550B A55B or GPT-5.4 nano?

GPT-5.4 nano is the better all-round choice, scoring 68/100 against Nemotron 3 Ultra 550B A55B (62). It leads on price and inputs & features. Nemotron 3 Ultra 550B A55B wins on context window. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.

Which is cheaper, Nemotron 3 Ultra 550B A55B or GPT-5.4 nano?

GPT-5.4 nano is cheaper at $0.20 input / $1.25 output per million tokens (official OpenAI API price). Nemotron 3 Ultra 550B A55B costs $0.50 input / $2.50 output per million tokens (official Nvidia API price). At a typical mix of three input tokens to one output token, that is $0.463 per million tokens for GPT-5.4 nano versus $1.00 for Nemotron 3 Ultra 550B A55B (2.2× as much).

Which scores higher on benchmarks?

Nemotron 3 Ultra 550B A55B scores higher on the Capabilities Index (ECI): Nemotron 3 Ultra 550B A55B 146.2 (#70 of 148) and GPT-5.4 nano 145.8 (#75 of 148). The confidence ranges of the top two overlap (143.9–148.1 vs 143.2–147.7), so treat the gap as small. On individual benchmarks: GPQA Diamond — Nemotron 3 Ultra 550B A55B 85.4%, GPT-5.4 nano 78.5%; OTIS Mock AIME 2024–2025 — GPT-5.4 nano 87.8%, Nemotron 3 Ultra 550B A55B 86.7%.

Which is better for coding?

There are no published SWE-bench Verified results for Nemotron 3 Ultra 550B A55B and GPT-5.4 nano yet, so there is no like-for-like coding score. On overall capability, Nemotron 3 Ultra 550B A55B leads, which tends to carry over to coding, but test on your own codebase. Both support tool calling for agent workflows.

Which has the bigger context window?

Nemotron 3 Ultra 550B A55B has the largest context window at 1,000,000 tokens, against 400,000 for GPT-5.4 nano. Maximum output per response: Nemotron 3 Ultra 550B A55B up to 128,000, GPT-5.4 nano up to 128,000 tokens.

Which can read images, PDFs, audio or video?

Nemotron 3 Ultra 550B A55B accepts text; GPT-5.4 nano accepts text and images. GPT-5.4 nano handles the widest range of inputs.

Are any of these open source?

Nemotron 3 Ultra 550B A55B publishes its weights and can be self-hosted; GPT-5.4 nano is proprietary.

Which is newer?

Nemotron 3 Ultra 550B A55B is the newest, released Jun 4, 2026. GPT-5.4 nano came out Mar 17, 2026. Knowledge cutoff: GPT-5.4 nano Aug 31, 2025.

How do you decide the winner?

Each model gets a 0–100 score on capability (50%, independent benchmark results); price (25%, blended price per million tokens (3 input : 1 output), log scale); inputs & features (15%, image, PDF, audio and video input, tool calling, structured output and reasoning); context window (10%, maximum tokens per request, log scale). Dimensions missing for any model are dropped and the remaining weights rescaled, so every model is judged on the same evidence. Specs and prices come from public model listings and the labs’ own API pages; capability scores come from independent benchmark runs. Data updated Oct 4, 2026.

05 — Keep comparing

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