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GPT-5.6 LunavsNVIDIA Nemotron 3 Ultra 550B-A55B NVFP4

GPT-5.6 Luna leads 1 of 1 shared benchmark. GPT-5.6 Luna has the larger context window (1.1M tokens).

Benchmarks from cited public sources; pricing from official pages; status from official provider feeds.

Shared benchmarks
1 – 0
GPT-5.6 Luna leads
Cheaper per token
list price, input + output
Larger context
GPT-5.6 Luna
1.1M tokens
Provider uptime (30d)
95.2096% · 100%
OpenAI · NVIDIA
GPT-5.6 Luna
OpenAI · released 2026-07-09
textvision
Context
1.1M
Max out
128K
Input /1M
$0.2
Output /1M
$1.2
Cached /1M
$0.02
Scores
8 · 6 core
NVIDIA Nemotron 3 Ultra 550B-A55B NVFP4
NVIDIA · released 2026-06-04
text
Context
1M
Max out
Input /1M
Output /1M
Cached /1M
Scores
6 · 4 core
Quality

Benchmark matrix

BenchmarkGPT-5.6 LunaNVIDIA Nemotron 3 Ultra 550B-A55B NVFP4ΔEdge
Reported by both · 1
GPQA Diamond92.3% 87.9% +4.4 ptGPT-5.6 Luna
Only GPT-5.6 Luna reports · 6
DeepSWE v1.167.2% not reported
FrontierMath Tier 4 v2 (Epoch AI run)61% epochnot reported
FrontierMath Tiers 1-3 v2 (Epoch AI run)82.1% epochnot reported
OTIS Mock AIME 2024-2025 (Epoch AI run)98.3% epochnot reported
SimpleQA Verified41% epochnot reported
SWE-Bench Pro62.7% not reported
Only NVIDIA Nemotron 3 Ultra 550B-A55B NVFP4 reports · 5
SWE-bench Verifiednot reported69.7%
Humanity's Last Exam (no tools)not reported26.1%
LMArena Elonot reported1444.7
BrowseCompnot reported41.4%
Terminal-Bench 2.1not reported53.9%
Scores tagged "epoch" or "matharena" are independent runs, used only where the lab has not published its own; ⚠ marks rows MathArena flags as released after the competition. Higher is better on every row. Δ is GPT-5.6 Luna minus NVIDIA Nemotron 3 Ultra 550B-A55B NVFP4 in the benchmark's own unit. "Not reported" means the lab has not published that figure; it is not a zero. ↗ opens the source.
Specs & pricing

Side by side

SpecGPT-5.6 LunaNVIDIA Nemotron 3 Ultra 550B-A55B NVFP4Edge
Context window1.1M tokens1M tokensGPT-5.6 Luna
Max output128K tokens
Input price / 1M$0.2
Output price / 1M$1.2
Cached input / 1M$0.02
Input + output / 1M
Lower is cheaper. List prices; batch, tool and regional fees excluded.
$1.4
Modalitiestext · visiontextGPT-5.6 Luna
Released2026-07-092026-06-04
Cited benchmark scores86
Reliability

Provider status

All providers
More matchups

GPT-5.6 Luna vs …

More matchups

NVIDIA Nemotron 3 Ultra 550B-A55B NVFP4 vs …

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