GPT-5.6 Luna (Low) vs Nemotron 3 Ultra 550B A55B (Reasoning)
Which is better for the money: GPT-5.6 Luna (Low) by OpenAI or Nemotron 3 Ultra 550B A55B (Reasoning) by NVIDIA? Intelligence, total benchmark cost, and end-to-end time from Artificial Analysis & other sources, snapshot 2026-10-27.
Trade-off
Verdict
Depends on your budget
Nemotron 3 Ultra 550B A55B (Reasoning) scores 1.9 points higher (22.9 vs 21.0) but costs 22× as much to run the benchmark ($596 vs $27.0; premium vs budget cost classes). They are not alternatives at one budget: pick Nemotron 3 Ultra 550B A55B (Reasoning) when you need intelligence above 21.0, and GPT-5.6 Luna (Low) when 21.0 is enough.
| Metric | GPT-5.6 Luna (Low) | Nemotron 3 Ultra 550B A55B (Reasoning) | Difference |
|---|---|---|---|
| Intelligence (higher is better) | 21.0 | 22.9 | +9.0% Nemotron 3 Ultra 550B… is 9.0% more intelligent |
| Total AA cost (lower is better) | $27.02 | $596.33 | +2107.0% Nemotron 3 Ultra 550B… is 22× more expensive |
| End-to-end time (lower is better) | 5.71s | 14.75s | +158.3% Nemotron 3 Ultra 550B… is 158.3% slower |
| Price per 1M tokens (in / out) | $0.20 / $1.20 | $0.60 / $2.70 | |
| Input modalities | Text, Image | Text |
Nemotron 3 Ultra 550B A55B (Reasoning) vs GPT-5.6 Luna (Low): 9.0% more intelligence, 2107.0% more cost to run the AA benchmark, and 158.3% slower end-to-end.
Today's Pareto frontier
Against the frontier
- GPT-5.6 Luna (Low) is off the frontier: at the same or lower cost, GPT-6 Luna (Low) scores 21.50 for $10.6.
- Nemotron 3 Ultra 550B A55B (Reasoning) is off the frontier: at the same or lower cost, GPT-6.1 Sol (High) scores 50.20 for $521.
GPT-5.6 Luna (Low)Nemotron 3 Ultra 550B A55B (Reasoning)Today's Pareto frontierOpen-weights frontierEvery other model
Matchup
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Accept: text/markdown or ?format=md returns this page as Markdown. JSON: /api/v1/compare/gpt-5-6-luna-low/nvidia-nemotron-3-ultra-550b-a55b · Markdown: /api/v1/compare/gpt-5-6-luna-low/nvidia-nemotron-3-ultra-550b-a55b?format=md · llms.txt · agent skill