Model comparison

GPT-6 Luna vs o3

GPT-6 Luna is the stronger model overall, scoring 53.3 to 47.5 on the Noometry Index.

Last verified . 31 shared benchmarks.

GPT-6 Luna OpenAI

53.3

Rank #36 Confirmed

o3 OpenAI

47.5

Rank #61 Confirmed

Summary

  • They share 31 benchmarks with published results for both. GPT-6 Luna scores higher in 6 categories and o3 in 4 categories; 10 gaps are clear of the uncertainty.
  • The widest gap is in math, where GPT-6 Luna leads 76.1 to 50.2.
  • The biggest single-benchmark swing is ARC-AGI-2: 59.3% for GPT-6 Luna and 6.5% for o3.
  • GPT-6 Luna is cheaper at $0.10 / $0.50 per million input/output tokens, against $2 / $8 for o3.
  • GPT-6 Luna accepts more context: 1.05M tokens versus 200K.

Side by side

GPT-6 Luna and o3 specifications
GPT-6 Lunao3
ProviderOpenAIOpenAI
Noometry Index53.347.5
Released2026-09-222025-04-16
WeightsProprietaryProprietary
Context window1.05M200K
Max output128K100K
Input $ / M tokens$0.10$2
Output $ / M tokens$0.50$8
Results tracked4263

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Category by category

Coding GPT-6 Luna leads

GPT-6 Luna: 55.5 (#25), o3: 46.8 (#64)

Coding benchmarks
BenchmarkGPT-6 Lunao3
LMArena Coding14391408
ALE-Bench1,577933.55
SWE-bench Verified—62.3%
DeepSWE66.6%—
FrontierCode42.4%—
SWE-bench Verified (bash only)—58.4%
Aider Polyglot—81.3%
LMArena WebDev1581—
SciCode54.6%—
GSO—8.8%
WeirdML—52.4%
CadEval—74%

Agentic & Tool Use o3 leads

GPT-6 Luna: 33.3 (#54), o3: 34.5 (#44)

Agentic & Tool Use benchmarks
BenchmarkGPT-6 Lunao3
APEX-Agents44.3%—
Berkeley Function Calling Leaderboard—63%
GDPval—30.8%
DeepResearch Bench—45.2%
OSWorld—23%
GDP.pdf23%—
LMArena Search—1144
METR Time Horizons—65.4%

Reasoning GPT-6 Luna leads

GPT-6 Luna: 48.2 (#41), o3: 32.0 (#78)

Reasoning benchmarks
BenchmarkGPT-6 Lunao3
ARC-AGI-259.3%6.5%
ARC-AGI-186.7%60.8%
CritPt19.4%1.4%
Chess Puzzles31%38%
LMArena Hard Prompts14111402
Mystery Game Puzzles7%29%
DTBench90.1%84.8%
LMCA44.5%39.7%
Epoch Capabilities Index156.28146.86
SimpleBench—53.1%
Kagi LLM Benchmark—67.6%
NYT Connections (extended)68.7%—
EnigmaEval—13.1%
ForecastBench—62.5

Math GPT-6 Luna leads

GPT-6 Luna: 76.1 (#15), o3: 50.2 (#58)

Math benchmarks
BenchmarkGPT-6 Lunao3
FrontierMath (Tiers 1-3)78.9%33.3%
OTIS Mock AIME 2024-202598.9%84.4%
LMArena Math14161426
FrontierMath Tier 456.1%—
ProofBench64%—
Omni-MATH—71.4%
MATH Level 5—97.8%
FrontierMath (Feb 2025 set)—18.7%
FrontierMath Tier 4 (v1)—2.1%

Knowledge GPT-6 Luna leads

GPT-6 Luna: 57.0 (#41), o3: 54.6 (#52)

Knowledge benchmarks
BenchmarkGPT-6 Lunao3
GPQA Diamond90.5%81.8%
SimpleQA Verified41.4%49.4%
LMArena Expert14441402
Humanity's Last Exam—20.3%
MMLU-Pro—85.9%
Confabulations—14.4%
GPQA (HELM)—75.3%

Multimodal GPT-6 Luna leads

GPT-6 Luna: 42.4 (#30), o3: 41.4 (#36)

Multimodal benchmarks
BenchmarkGPT-6 Lunao3
LMArena Vision12171214
GeoBench—74%
VPCT—52%
Blueprint-Bench 231.2%—
Furniture Assembly44.2%—

Multilingual o3 leads

GPT-6 Luna: 50.5 (#117), o3: 51.7 (#105)

Multilingual benchmarks
BenchmarkGPT-6 Lunao3
LMArena Non-English13861401
LMArena Chinese14331437
LMArena French14201430
LMArena German13691420
LMArena Japanese13691403
LMArena Korean13601370
LMArena Russian13941406
LMArena Spanish13931395

Instruction Following GPT-6 Luna leads

GPT-6 Luna: 74.3 (#99), o3: 72.8 (#127)

Instruction Following benchmarks
BenchmarkGPT-6 Lunao3
LMArena Instruction Following14091368
IFEval—86.9%

Long Context o3 leads

GPT-6 Luna: 43.0 (#111), o3: 53.3 (#6)

Long Context benchmarks
BenchmarkGPT-6 Lunao3
LMArena Longer Query14091372
Fiction.LiveBench—88.9%
CL-bench—17.8%

Writing & Preference o3 leads

GPT-6 Luna: 58.3 (#119), o3: 63.5 (#64)

Writing & Preference benchmarks
BenchmarkGPT-6 Lunao3
LMArena Text13911410
LMArena Creative Writing13631359
LMArena Multi-Turn13961405
Short-Story Creative Writing—83.9%
EQ-Bench Creative Writing—1676
WildBench—86.1%

Frequently asked questions

Is GPT-6 Luna better than o3?

GPT-6 Luna is the stronger model overall, scoring 53.3 to 47.5 on the Noometry Index.

Which is cheaper, GPT-6 Luna or o3?

GPT-6 Luna is cheaper. It lists at $0.10 per million input tokens and $0.50 per million output tokens; o3 lists at $2 and $8.

Is GPT-6 Luna or o3 better for coding?

GPT-6 Luna scores higher on coding benchmarks: 55.5 versus 46.8 in the Noometry coding category.

Which has the bigger context window?

GPT-6 Luna does, with 1.05M tokens against 200K.

How many benchmarks do GPT-6 Luna and o3 share?

31 benchmarks have published results for both models. GPT-6 Luna has 42 scored results on Noometry and o3 has 63.

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