Noometry

Model comparison

GPT-5.5 Instant vs o3

o3 is the stronger model overall, scoring 47.4 to 42.5 on the Noometry Index.

Last verified . 24 shared benchmarks.

GPT-5.5 Instant OpenAI

42.5

Rank #99 Confirmed

o3 OpenAI

47.4

Rank #53 Confirmed

Summary

  • They share 24 benchmarks with published results for both. GPT-5.5 Instant scores higher in 2 categories and o3 in 7 categories; 9 gaps are clear of the uncertainty.
  • The widest gap is in math, where o3 leads 48.9 to 26.1.
  • The biggest single-benchmark swing is Chess Puzzles: 12% for GPT-5.5 Instant and 38% for o3.

Side by side

GPT-5.5 Instanto3
ProviderOpenAIOpenAI
Noometry Index42.547.4
Released2026-05-052025-04-16
WeightsProprietaryProprietary
Context window—200K
Max output—100K
Input $ / M tokens—$2
Output $ / M tokens—$8
Results tracked2763

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Category by category

Coding o3 leads

GPT-5.5 Instant: 43.7 (#73), o3: 47.3 (#57)

BenchmarkGPT-5.5 Instanto3
LMArena Coding14331408
SWE-bench Verified—62.3%
SWE-bench Verified (bash only)—58.4%
Aider Polyglot—81.3%
SciCode48.6%—
GSO—8.8%
WeirdML—52.4%
CadEval—74%
ALE-Bench—933.55

Agentic & Tool Use Not comparable

GPT-5.5 Instant: —, o3: 34.3 (#42)

BenchmarkGPT-5.5 Instanto3
Berkeley Function Calling Leaderboard—63%
GDPval—30.8%
DeepResearch Bench—45.2%
OSWorld—23%
LMArena Search—1144
METR Time Horizons—65.4%

Reasoning o3 leads

GPT-5.5 Instant: 24.2 (#149), o3: 32.1 (#66)

BenchmarkGPT-5.5 Instanto3
CritPt0%1.4%
Chess Puzzles12%38%
LMArena Hard Prompts14261402
Epoch Capabilities Index142.48146.88
ARC-AGI-2—6.5%
SimpleBench—53.1%
Kagi LLM Benchmark—67.6%
ARC-AGI-1—60.8%
EnigmaEval—13.1%
Mystery Game Puzzles—29%
DTBench—84.8%
LMCA—39.7%
ForecastBench—62.5

Math o3 leads

GPT-5.5 Instant: 26.1 (#241), o3: 48.9 (#49)

BenchmarkGPT-5.5 Instanto3
FrontierMath (Tiers 1-3)26.3%33.3%
OTIS Mock AIME 2024-202568.1%84.4%
LMArena Math14201426
FrontierMath Tier 42.4%—
Omni-MATH—71.4%
MATH Level 5—97.8%
FrontierMath (Feb 2025 set)—18.7%
FrontierMath Tier 4 (v1)—2.1%

Knowledge o3 leads

GPT-5.5 Instant: 48.9 (#68), o3: 54.5 (#47)

BenchmarkGPT-5.5 Instanto3
GPQA Diamond82.5%81.8%
LMArena Expert14091403
Humanity's Last Exam—20.3%
SimpleQA Verified—49.4%
MMLU-Pro—85.9%
Confabulations—14.4%
GPQA (HELM)—75.3%

Multimodal o3 leads

GPT-5.5 Instant: 39.3 (#48), o3: 40.7 (#35)

BenchmarkGPT-5.5 Instanto3
LMArena Vision12501214
GeoBench—74%
VPCT—52%
LMArena Document1403—

Multilingual GPT-5.5 Instant leads

GPT-5.5 Instant: 53.0 (#76), o3: 51.9 (#99)

BenchmarkGPT-5.5 Instanto3
LMArena Non-English14171402
LMArena Chinese14571438
LMArena French14281430
LMArena German14101420
LMArena Japanese14081404
LMArena Korean13931371
LMArena Russian14301407
LMArena Spanish14301395

Instruction Following GPT-5.5 Instant leads

GPT-5.5 Instant: 74.4 (#94), o3: 73.0 (#122)

BenchmarkGPT-5.5 Instanto3
LMArena Instruction Following14071368
IFEval—86.9%

Long Context o3 leads

GPT-5.5 Instant: 43.4 (#92), o3: 53.2 (#6)

BenchmarkGPT-5.5 Instanto3
LMArena Longer Query14221372
Fiction.LiveBench—88.9%
CL-bench—17.8%

Writing & Preference o3 leads

GPT-5.5 Instant: 62.0 (#81), o3: 63.7 (#62)

BenchmarkGPT-5.5 Instanto3
LMArena Text14191410
LMArena Creative Writing14201359
LMArena Multi-Turn14341405
Short-Story Creative Writing—83.9%
EQ-Bench Creative Writing—1676
WildBench—86.1%

Frequently asked questions

Is GPT-5.5 Instant better than o3?

o3 is the stronger model overall, scoring 47.4 to 42.5 on the Noometry Index.

Is GPT-5.5 Instant or o3 better for coding?

o3 scores higher on coding benchmarks: 47.3 versus 43.7 in the Noometry coding category.

How many benchmarks do GPT-5.5 Instant and o3 share?

24 benchmarks have published results for both models. GPT-5.5 Instant has 27 scored results on Noometry and o3 has 63.

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