Noometry

Model comparison

Claude Sonnet 5.5 vs GPT-5 Pro

Claude Sonnet 5.5 is the stronger model overall, scoring 61.9 to 46.4 on the Noometry Index.

Last verified . 3 shared benchmarks.

Claude Sonnet 5.5 Anthropic

61.9

Rank #10 Confirmed

GPT-5 Pro OpenAI

46.4

Rank #64 Confirmed

Summary

  • They share 3 benchmarks with published results for both. Claude Sonnet 5.5 scores higher in 4 categories and GPT-5 Pro in 0 categories; 4 gaps are clear of the uncertainty.
  • The widest gap is in math, where Claude Sonnet 5.5 leads 87.9 to 48.5.
  • The biggest single-benchmark swing is FrontierMath Tier 4: 80.5% for Claude Sonnet 5.5 and 19.5% for GPT-5 Pro.
  • Claude Sonnet 5.5 is cheaper at $2 / $10 per million input/output tokens, against $15 / $120 for GPT-5 Pro.
  • Claude Sonnet 5.5 accepts more context: 1M tokens versus 400K.

Side by side

Claude Sonnet 5.5GPT-5 Pro
ProviderAnthropicOpenAI
Noometry Index61.946.4
Released2026-09-282025-10-06
WeightsProprietaryProprietary
Context window1M400K
Max output128K272K
Input $ / M tokens$2$15
Output $ / M tokens$10$120
Results tracked3212

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Category by category

Coding Claude Sonnet 5.5 leads

Claude Sonnet 5.5: 67.3 (#6), GPT-5 Pro: 44.0 (#80)

BenchmarkClaude Sonnet 5.5GPT-5 Pro
FrontierCode52.1%—
CursorBench55.5%—
LMArena WebDev1774—
FrontierSWE61.9%—
SciCode61%—
WeirdML—60.4%
LMArena Coding1513—
ALE-Bench1,819—
AlgoTune—1.31

Agentic & Tool Use Not comparable

Claude Sonnet 5.5: 45.0 (#16), GPT-5 Pro: —

BenchmarkClaude Sonnet 5.5GPT-5 Pro
APEX-Agents75.5%—

Reasoning Claude Sonnet 5.5 leads

Claude Sonnet 5.5: 54.0 (#28), GPT-5 Pro: 38.9 (#62)

BenchmarkClaude Sonnet 5.5GPT-5 Pro
Epoch Capabilities Index165.03150.28
ARC-AGI-2—18.3%
SimpleBench—61.6%
Kagi LLM Benchmark—76.8%
NYT Connections (extended)80.5%—
ARC-AGI-1—70.2%
CritPt31.4%—
EnigmaEval—18.8%
LMArena Hard Prompts1495—
Mystery Game Puzzles65%—

Math Claude Sonnet 5.5 leads

Claude Sonnet 5.5: 87.9 (#6), GPT-5 Pro: 48.5 (#63)

BenchmarkClaude Sonnet 5.5GPT-5 Pro
FrontierMath (Tiers 1-3)88.8%55.8%
FrontierMath Tier 480.5%19.5%
OTIS Mock AIME 2024-2025100%—
ProofBench100%—
LMArena Math1510—
FrontierMath Erdős2.9%—
FrontierMath Tier 4 (v1)—14.6%

Knowledge Claude Sonnet 5.5 leads

Claude Sonnet 5.5: 66.0 (#12), GPT-5 Pro: 56.7 (#42)

BenchmarkClaude Sonnet 5.5GPT-5 Pro
GPQA Diamond95.6%—
Humanity's Last Exam—31.6%
SimpleQA Verified46.5%—
LMArena Expert1540—

Multimodal Not comparable

Claude Sonnet 5.5: 51.5 (#6), GPT-5 Pro: —

BenchmarkClaude Sonnet 5.5GPT-5 Pro
LMArena Vision1289—
Furniture Assembly75%—

Multilingual Not comparable

Claude Sonnet 5.5: 55.3 (#30), GPT-5 Pro: —

BenchmarkClaude Sonnet 5.5GPT-5 Pro
LMArena Non-English1452—
LMArena Chinese1522—
LMArena Russian1451—

Instruction Following Not comparable

Claude Sonnet 5.5: 78.3 (#11), GPT-5 Pro: —

BenchmarkClaude Sonnet 5.5GPT-5 Pro
LMArena Instruction Following1495—

Long Context Not comparable

Claude Sonnet 5.5: 45.9 (#28), GPT-5 Pro: —

BenchmarkClaude Sonnet 5.5GPT-5 Pro
LMArena Longer Query1498—

Writing & Preference Not comparable

Claude Sonnet 5.5: 66.0 (#40), GPT-5 Pro: —

BenchmarkClaude Sonnet 5.5GPT-5 Pro
LMArena Text1471—
LMArena Creative Writing1465—
LMArena Multi-Turn1474—

Frequently asked questions

Is Claude Sonnet 5.5 better than GPT-5 Pro?

Claude Sonnet 5.5 is the stronger model overall, scoring 61.9 to 46.4 on the Noometry Index.

Which is cheaper, Claude Sonnet 5.5 or GPT-5 Pro?

Claude Sonnet 5.5 is cheaper. It lists at $2 per million input tokens and $10 per million output tokens; GPT-5 Pro lists at $15 and $120.

Is Claude Sonnet 5.5 or GPT-5 Pro better for coding?

Claude Sonnet 5.5 scores higher on coding benchmarks: 67.3 versus 44.0 in the Noometry coding category.

Which has the bigger context window?

Claude Sonnet 5.5 does, with 1M tokens against 400K.

How many benchmarks do Claude Sonnet 5.5 and GPT-5 Pro share?

3 benchmarks have published results for both models. Claude Sonnet 5.5 has 32 scored results on Noometry and GPT-5 Pro has 12.

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