Noometry

Model comparison

GPT-5.5 Instant vs Kimi K3

Kimi K3 is the stronger model overall, scoring 59.5 to 42.5 on the Noometry Index.

Last verified . 25 shared benchmarks.

GPT-5.5 Instant OpenAI

42.5

Rank #99 Confirmed

Kimi K3 Moonshot AI

59.5

Rank #12 Confirmed

Summary

  • They share 25 benchmarks with published results for both. GPT-5.5 Instant scores higher in 1 category and Kimi K3 in 8 categories; 8 gaps are clear of the uncertainty.
  • The widest gap is in math, where Kimi K3 leads 74.0 to 26.1.
  • The biggest single-benchmark swing is FrontierMath (Tiers 1-3): 26.3% for GPT-5.5 Instant and 72.2% for Kimi K3.
  • Kimi K3 has downloadable open weights; the other is API-only.

Side by side

GPT-5.5 InstantKimi K3
ProviderOpenAIMoonshot AI
Noometry Index42.559.5
Released2026-05-052026-07-16
WeightsProprietaryOpen
Context window—1.05M
Max output—1.05M
Input $ / M tokens—$3
Output $ / M tokens—$15
Results tracked2753

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Category by category

Coding Kimi K3 leads

GPT-5.5 Instant: 43.7 (#73), Kimi K3: 60.6 (#8)

BenchmarkGPT-5.5 InstantKimi K3
SciCode48.6%59.5%
LMArena Coding14331509
DeepSWE—68.5%
FrontierCode—44.2%
LMArena WebDev—1659
FrontierSWE—25.9%
WeirdML—82.6%
ALE-Bench—1,524

Agentic & Tool Use Not comparable

GPT-5.5 Instant: —, Kimi K3: 41.8 (#19)

BenchmarkGPT-5.5 InstantKimi K3
APEX-Agents—50.6%
τ²-bench Banking—37.1%
PostTrainBench—32%
GBAEval—48.3%
GDP.pdf—19%
Vending-Bench 2—5,165

Reasoning Kimi K3 leads

GPT-5.5 Instant: 24.2 (#149), Kimi K3: 63.0 (#15)

BenchmarkGPT-5.5 InstantKimi K3
CritPt0%23.4%
Chess Puzzles12%39%
LMArena Hard Prompts14261495
Epoch Capabilities Index142.48157.68
ARC-AGI-2—60.4%
SimpleBench—60.7%
NYT Connections (extended)—93.6%
ARC-AGI-1—94.5%
Mystery Game Puzzles—26%
DTBench—91.2%
LMCA—52.7%
Surface Evolver Bench—95%
ForecastBench—61.1

Math Kimi K3 leads

GPT-5.5 Instant: 26.1 (#241), Kimi K3: 74.0 (#13)

BenchmarkGPT-5.5 InstantKimi K3
FrontierMath (Tiers 1-3)26.3%72.2%
FrontierMath Tier 42.4%39%
OTIS Mock AIME 2024-202568.1%97.2%
LMArena Math14201493
MathArena Final-Answer Competitions—87.8%
ProofBench—87%

Knowledge Kimi K3 leads

GPT-5.5 Instant: 48.9 (#68), Kimi K3: 63.2 (#19)

BenchmarkGPT-5.5 InstantKimi K3
GPQA Diamond82.5%93.1%
LMArena Expert14091520
SimpleQA Verified—50.6%

Multimodal Too close to call

GPT-5.5 Instant: 39.3 (#48), Kimi K3: 38.4 (#58)

BenchmarkGPT-5.5 InstantKimi K3
LMArena Vision1250—
Blueprint-Bench 2—29.5%
Furniture Assembly—34.2%
LMArena Document1403—

Multilingual Kimi K3 leads

GPT-5.5 Instant: 53.0 (#76), Kimi K3: 56.5 (#20)

BenchmarkGPT-5.5 InstantKimi K3
LMArena Non-English14171466
LMArena Chinese14571528
LMArena French14281488
LMArena German14101474
LMArena Japanese14081492
LMArena Korean13931465
LMArena Russian14301481
LMArena Spanish14301478

Instruction Following Kimi K3 leads

GPT-5.5 Instant: 74.4 (#94), Kimi K3: 77.8 (#13)

BenchmarkGPT-5.5 InstantKimi K3
LMArena Instruction Following14071481

Long Context Kimi K3 leads

GPT-5.5 Instant: 43.4 (#92), Kimi K3: 45.8 (#27)

BenchmarkGPT-5.5 InstantKimi K3
LMArena Longer Query14221494

Writing & Preference Kimi K3 leads

GPT-5.5 Instant: 62.0 (#81), Kimi K3: 76.7 (#4)

BenchmarkGPT-5.5 InstantKimi K3
LMArena Text14191476
LMArena Creative Writing14201452
LMArena Multi-Turn14341488
EQ-Bench Creative Writing—2082
EQ-Bench 4—1339

Frequently asked questions

Is GPT-5.5 Instant better than Kimi K3?

Kimi K3 is the stronger model overall, scoring 59.5 to 42.5 on the Noometry Index.

Is GPT-5.5 Instant or Kimi K3 better for coding?

Kimi K3 scores higher on coding benchmarks: 60.6 versus 43.7 in the Noometry coding category.

How many benchmarks do GPT-5.5 Instant and Kimi K3 share?

25 benchmarks have published results for both models. GPT-5.5 Instant has 27 scored results on Noometry and Kimi K3 has 53.

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