Model comparison

Chatgpt 4o Latest 20250326 vs GPT-5.5

GPT-5.5 is the stronger model overall, scoring 63.4 to 43.8 on the Noometry Index.

Last verified . 20 shared benchmarks.

Chatgpt 4o Latest 20250326 OpenAI

43.8

Rank #82 Confirmed

GPT-5.5 OpenAI

63.4

Rank #9 Confirmed

Summary

  • They share 20 benchmarks with published results for both. Chatgpt 4o Latest 20250326 scores higher in 0 categories and GPT-5.5 in 9 categories; 9 gaps are clear of the uncertainty.
  • The widest gap is in math, where GPT-5.5 leads 81.7 to 38.6.
  • The biggest single-benchmark swing is Kagi LLM Benchmark: 75% for Chatgpt 4o Latest 20250326 and 88.8% for GPT-5.5.

Side by side

Chatgpt 4o Latest 20250326 and GPT-5.5 specifications
Chatgpt 4o Latest 20250326GPT-5.5
ProviderOpenAIOpenAI
Noometry Index43.863.4
Released—2026-04-23
WeightsProprietaryProprietary
Context window—1.05M
Max output—128K
Input $ / M tokens—$5
Output $ / M tokens—$30
Results tracked2171

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Category by category

Coding GPT-5.5 leads

Chatgpt 4o Latest 20250326: 41.6 (#122), GPT-5.5: 58.2 (#17)

Coding benchmarks
BenchmarkChatgpt 4o Latest 20250326GPT-5.5
LMArena Coding14131494
SWE-bench Verified—80.6%
DeepSWE—67%
FrontierCode—43%
LMArena WebDev—1513
SciCode—56.1%
GSO—40.2%
WeirdML—84.9%
MirrorCode—10%
ALE-Bench—1,943

Agentic & Tool Use Not comparable

Chatgpt 4o Latest 20250326: —, GPT-5.5: 50.7 (#6)

Agentic & Tool Use benchmarks
BenchmarkChatgpt 4o Latest 20250326GPT-5.5
Terminal-Bench—84.7%
APEX-Agents—55.1%
OSWorld 2.0—13%
Remote Labor Index—6.3%
τ²-bench Banking—44.6%
DeepResearch Bench—54%
PostTrainBench—27.2%
ExploitBench—47.4%
GBAEval—53.2%
GDP.pdf—26%
LMArena Search—1242
Vending-Bench 2—7,524

Reasoning GPT-5.5 leads

Chatgpt 4o Latest 20250326: 33.8 (#71), GPT-5.5: 72.8 (#11)

Reasoning benchmarks
BenchmarkChatgpt 4o Latest 20250326GPT-5.5
Kagi LLM Benchmark75%88.8%
LMArena Hard Prompts14241489
ARC-AGI-2—85%
SimpleBench—69%
NYT Connections (extended)—96.2%
ARC-AGI-1—95%
CritPt—27.1%
Chess Puzzles—54%
EBR-Bench—34.3%
Mystery Game Puzzles—56%
DTBench—96%
LMCA—54.3%
Surface Evolver Bench—88.1%
Bench to the Future 3—0.14
Epoch Capabilities Index—159.1
ForecastBench—60.6

Math GPT-5.5 leads

Chatgpt 4o Latest 20250326: 38.6 (#134), GPT-5.5: 81.7 (#11)

Knowledge GPT-5.5 leads

Chatgpt 4o Latest 20250326: 39.2 (#137), GPT-5.5: 64.4 (#17)

Knowledge benchmarks
BenchmarkChatgpt 4o Latest 20250326GPT-5.5
LMArena Expert14011508
GPQA Diamond—94%
SimpleQA Verified—63%
Confabulations16.6%—
Vectara Hallucination Rate—9.3%

Multimodal GPT-5.5 leads

Chatgpt 4o Latest 20250326: 39.6 (#58), GPT-5.5: 46.9 (#12)

Multimodal benchmarks
BenchmarkChatgpt 4o Latest 20250326GPT-5.5
LMArena Vision12431297
Blueprint-Bench 2—36.2%
Furniture Assembly—44.2%
LMArena Document—1486

Multilingual GPT-5.5 leads

Chatgpt 4o Latest 20250326: 52.9 (#76), GPT-5.5: 56.4 (#20)

Multilingual benchmarks
BenchmarkChatgpt 4o Latest 20250326GPT-5.5
LMArena Non-English14191467
LMArena Chinese14571533
LMArena French14461486
LMArena German14231480
LMArena Japanese14051498
LMArena Korean13961460
LMArena Russian14291473
LMArena Spanish14341468

Instruction Following GPT-5.5 leads

Chatgpt 4o Latest 20250326: 74.0 (#107), GPT-5.5: 77.5 (#18)

Instruction Following benchmarks
BenchmarkChatgpt 4o Latest 20250326GPT-5.5
LMArena Instruction Following14031479

Long Context GPT-5.5 leads

Chatgpt 4o Latest 20250326: 43.1 (#107), GPT-5.5: 48.3 (#12)

Long Context benchmarks
BenchmarkChatgpt 4o Latest 20250326GPT-5.5
LMArena Longer Query14131484
CL-bench Life—22.2%

Writing & Preference GPT-5.5 leads

Chatgpt 4o Latest 20250326: 62.6 (#72), GPT-5.5: 72.7 (#13)

Writing & Preference benchmarks
BenchmarkChatgpt 4o Latest 20250326GPT-5.5
LMArena Text14291472
LMArena Creative Writing14051455
EQ-Bench Creative Writing15011844
LMArena Multi-Turn14541476
EQ-Bench 4—1315

Frequently asked questions

Is Chatgpt 4o Latest 20250326 better than GPT-5.5?

GPT-5.5 is the stronger model overall, scoring 63.4 to 43.8 on the Noometry Index.

Is Chatgpt 4o Latest 20250326 or GPT-5.5 better for coding?

GPT-5.5 scores higher on coding benchmarks: 58.2 versus 41.6 in the Noometry coding category.

How many benchmarks do Chatgpt 4o Latest 20250326 and GPT-5.5 share?

20 benchmarks have published results for both models. Chatgpt 4o Latest 20250326 has 21 scored results on Noometry and GPT-5.5 has 71.

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