GPT-5.6 Luna

OpenAI · Closed weights · Released Jul 9, 2026 · $0.20 in · $1.20 out per 1M tokens

41Overall · rank 25

Score by job

52 · rank 21 · 3 of 5 benchmarks

Benchmark	Result	Variant	z
DeepSWE	67.2%	gpt-5.6-luna_max	0.64
FrontierCode	39.8%	gpt-5.6-luna_unknown	0.03
LMArena Coding	1463 rating	gpt-5.6-luna-xhigh	-1.32

Not enough data · 0 of 4 benchmarks

29 · rank 30 · 3 of 4 benchmarks

Benchmark	Result	Variant	z
GPQA Diamond	91.6%	gpt-5.6-luna_max	0.02
ARC-AGI-2	59.5%	gpt-5.6-luna_max	-0.20
SimpleBench	46.8%	gpt-5.6-luna_unknown	-1.86

58 · rank 15 · 5 of 5 benchmarks

Benchmark	Result	Variant	z
FrontierMath Tiers 1–3	82.1%	gpt-5.6-luna_max	0.97
FrontierMath Tier 4	61.0%	gpt-5.6-luna_max	0.84
OTIS Mock AIME	98.3%	gpt-5.6-luna_max	0.68
ProofBench	60.0%	gpt-5.6-luna_max	0.48
LMArena Math	1457 rating	gpt-5.6-luna-xhigh	-0.86

35 · rank 39 · 2 of 2 benchmarks

Benchmark	Result	Variant	z
LMArena Creative Writing	1396 rating	gpt-5.6-luna-xhigh	-1.65
LMArena Instruction Following	1435 rating	gpt-5.6-luna-xhigh	-1.09

33 · rank 28 · 1 of 1 benchmarks

Benchmark	Result	Variant	z
LMArena WebDev	1519 rating	gpt-5.6-luna-xhigh (codex-harness)	-0.38