GPT 5.6 Luna XhighvsNvidia Nemotron 3 Ultra 550b A55b Nvfp4
GPT 5.6 Luna Xhigh leads the overall Podium Score by 2.0 points (73.0 vs 71.0).Category wins: GPT 5.6 Luna Xhigh 0 — 0 Nvidia Nemotron 3 Ultra 550b A55b Nvfp4.Nvidia Nemotron 3 Ultra 550b A55b Nvfp4 is the cheaper pick ($3/M vs $10/M per 1M output tokens). GPT 5.6 Luna Xhigh is faster (50 t/s vs 50 t/s).
Key VerdictAggregated 2026 Benchmark Analysis
GPT 5.6 Luna Xhigh is rated higher overall with a Podium Score of 73.0 (vs 71.0 for Nvidia Nemotron 3 Ultra 550b A55b Nvfp4). Both models show closely matched capabilities across domain benchmarks.
Coding & Engineering
Comparable
Inference Speed
GPT 5.6 Luna Xhigh (50 t/s)
Cost Efficiency
Nvidia Nemotron 3 Ultra 550b A55b Nvfp4 ($3/M/M)
| Metric | GPT 5.6 Luna Xhigh | Nvidia Nemotron 3 Ultra 550b A55b Nvfp4 |
|---|---|---|
| Podium Score | 73.0 ▲ | 71.0 |
| Arena Elo | — | — |
| Intelligence Index | — | — |
| Coding | — | — |
| Math | — | — |
| Reasoning | — | — |
| Agentic | — | — |
| Knowledge | — | — |
| Multimodal | — | — |
| Long-context | — | — |
| Output speed | 50 t/s | 50 t/s |
| Output price | $10/M | $3/M ▲ |
| Context window | 128K | 128K |
Scores aggregated from five independent leaderboards. See Methodology. More head-to-heads: GPT 5.6 Luna Xhigh vs Claude Mythos · GPT 5.6 Luna Xhigh vs Claude Fable 5 · GPT 5.6 Luna Xhigh vs Kimi K3 · GPT 5.6 Luna Xhigh vs Claude Opus 5