Noometry

Model comparison

Gemini 3.8 Flash vs GPT-5.5 Instant

Gemini 3.8 Flash is the stronger model overall, scoring 61.8 to 42.7 on the Noometry Index.

Last verified . 26 shared benchmarks.

Gemini 3.8 Flash Google

61.8

Rank #11 Confirmed

GPT-5.5 Instant OpenAI

42.7

Rank #110 Confirmed

Summary

  • They share 26 benchmarks with published results for both. Gemini 3.8 Flash scores higher in 9 categories and GPT-5.5 Instant in 0 categories; 8 gaps are clear of the uncertainty.
  • The widest gap is in reasoning, where Gemini 3.8 Flash leads 76.9 to 24.9.
  • The biggest single-benchmark swing is Chess Puzzles: 61% for Gemini 3.8 Flash and 12% for GPT-5.5 Instant.

Side by side

Gemini 3.8 FlashGPT-5.5 Instant
ProviderGoogleOpenAI
Noometry Index61.842.7
Released2026-09-022026-05-05
WeightsProprietaryProprietary
Context window1.05M—
Max output66K—
Input $ / M tokens$0.75—
Output $ / M tokens$3.75—
Results tracked5027

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Category by category

Coding Gemini 3.8 Flash leads

Gemini 3.8 Flash: 59.2 (#15), GPT-5.5 Instant: 44.3 (#74)

BenchmarkGemini 3.8 FlashGPT-5.5 Instant
SciCode56.6%48.6%
LMArena Coding15101433
DeepSWE73.8%—
FrontierCode41.2%—
CursorBench39.6%—
LMArena WebDev1584—
FrontierSWE19.6%—
WeirdML84.8%—
ALE-Bench1,270—

Agentic & Tool Use Not comparable

Gemini 3.8 Flash: 41.8 (#21), GPT-5.5 Instant: —

BenchmarkGemini 3.8 FlashGPT-5.5 Instant
APEX-Agents64.3%—
Remote Labor Index5.8%—
GDP.pdf23.4%—
Vending-Bench 25,094—

Reasoning Gemini 3.8 Flash leads

Gemini 3.8 Flash: 76.9 (#5), GPT-5.5 Instant: 24.9 (#155)

BenchmarkGemini 3.8 FlashGPT-5.5 Instant
CritPt18.3%0%
Chess Puzzles61%12%
LMArena Hard Prompts15081426
Epoch Capabilities Index156.71142.52
ARC-AGI-289.2%—
NYT Connections (extended)97.4%—
ARC-AGI-198.5%—
Mystery Game Puzzles47%—
DTBench95.7%—
LMCA52.9%—
Surface Evolver Bench76.9%—

Math Gemini 3.8 Flash leads

Gemini 3.8 Flash: 65.3 (#28), GPT-5.5 Instant: 26.5 (#259)

BenchmarkGemini 3.8 FlashGPT-5.5 Instant
FrontierMath (Tiers 1-3)68.4%26.3%
FrontierMath Tier 422%2.4%
OTIS Mock AIME 2024-202598.9%68.1%
LMArena Math15281420
ProofBench48%—

Knowledge Gemini 3.8 Flash leads

Gemini 3.8 Flash: 74.8 (#2), GPT-5.5 Instant: 48.9 (#74)

BenchmarkGemini 3.8 FlashGPT-5.5 Instant
GPQA Diamond95.4%82.5%
LMArena Expert15241409
Humanity's Last Exam44.5%—
SimpleQA Verified69.7%—

Multimodal Too close to call

Gemini 3.8 Flash: 40.7 (#45), GPT-5.5 Instant: 40.0 (#52)

BenchmarkGemini 3.8 FlashGPT-5.5 Instant
LMArena Vision13141250
Blueprint-Bench 238.6%—
Furniture Assembly31.7%—
LMArena Document—1403

Multilingual Gemini 3.8 Flash leads

Gemini 3.8 Flash: 58.0 (#5), GPT-5.5 Instant: 52.8 (#80)

BenchmarkGemini 3.8 FlashGPT-5.5 Instant
LMArena Non-English14911417
LMArena Chinese15541456
LMArena French14981428
LMArena German14931411
LMArena Japanese15021408
LMArena Korean14591392
LMArena Russian15151431
LMArena Spanish14851429

Instruction Following Gemini 3.8 Flash leads

Gemini 3.8 Flash: 78.0 (#13), GPT-5.5 Instant: 74.2 (#100)

BenchmarkGemini 3.8 FlashGPT-5.5 Instant
LMArena Instruction Following14901406

Long Context Gemini 3.8 Flash leads

Gemini 3.8 Flash: 46.3 (#24), GPT-5.5 Instant: 43.4 (#96)

BenchmarkGemini 3.8 FlashGPT-5.5 Instant
LMArena Longer Query15081422

Writing & Preference Gemini 3.8 Flash leads

Gemini 3.8 Flash: 72.2 (#15), GPT-5.5 Instant: 61.8 (#85)

BenchmarkGemini 3.8 FlashGPT-5.5 Instant
LMArena Text14991419
LMArena Creative Writing14921419
LMArena Multi-Turn15011433
EQ-Bench Creative Writing1748—

Frequently asked questions

Is Gemini 3.8 Flash better than GPT-5.5 Instant?

Gemini 3.8 Flash is the stronger model overall, scoring 61.8 to 42.7 on the Noometry Index.

Is Gemini 3.8 Flash or GPT-5.5 Instant better for coding?

Gemini 3.8 Flash scores higher on coding benchmarks: 59.2 versus 44.3 in the Noometry coding category.

How many benchmarks do Gemini 3.8 Flash and GPT-5.5 Instant share?

26 benchmarks have published results for both models. Gemini 3.8 Flash has 50 scored results on Noometry and GPT-5.5 Instant has 27.

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