Noometry

Model comparison

Claude Opus 4 vs Claude Opus 4.5

Claude Opus 4.5 is the stronger model overall, scoring 50.5 to 43.1 on the Noometry Index.

Last verified . 44 shared benchmarks.

Claude Opus 4 Anthropic

43.1

Rank #100 Confirmed

Claude Opus 4.5 Anthropic

50.5

Rank #47 Confirmed

Summary

  • They share 44 benchmarks with published results for both. Claude Opus 4 scores higher in 2 categories and Claude Opus 4.5 in 8 categories; 8 gaps are clear of the uncertainty.
  • The widest gap is in reasoning, where Claude Opus 4.5 leads 42.6 to 27.3.
  • The biggest single-benchmark swing is ARC-AGI-1: 35.7% for Claude Opus 4 and 80% for Claude Opus 4.5.
  • Claude Opus 4.5 is cheaper at $5 / $25 per million input/output tokens, against $15 / $75 for Claude Opus 4.

Side by side

Claude Opus 4Claude Opus 4.5
ProviderAnthropicAnthropic
Noometry Index43.150.5
Released2025-05-222025-11-01
WeightsProprietaryProprietary
Context window200K200K
Max output32K64K
Input $ / M tokens$15$5
Output $ / M tokens$75$25
Results tracked5669

Sponsored placements are available on pages like this one. Advertise on Noometry

Category by category

Coding Claude Opus 4.5 leads

Claude Opus 4: 47.2 (#62), Claude Opus 4.5: 54.8 (#27)

BenchmarkClaude Opus 4Claude Opus 4.5
SWE-bench Verified70.7%76.7%
SWE-bench Verified (bash only)67.6%76.8%
GSO6.9%26.5%
WeirdML43.7%63.7%
LMArena Coding14421504
AlgoTune1.331.77
Aider Polyglot72%—
LMArena WebDev—1494
SWE-bench Multilingual—70.7%
ALE-Bench—1,025

Agentic & Tool Use Claude Opus 4.5 leads

Claude Opus 4: 34.8 (#42), Claude Opus 4.5: 47.3 (#12)

BenchmarkClaude Opus 4Claude Opus 4.5
Cybench38%82%
DeepResearch Bench46.8%54.8%
LMArena Search11271180
METR Time Horizons63.9%75%
Terminal-Bench—63.1%
Berkeley Function Calling Leaderboard—77.5%
GDPval—45.5%
Remote Labor Index—3.8%
τ²-bench Airline—84%
τ²-bench Banking—24.7%
τ²-bench Retail—79.6%
τ²-bench Telecom—92.3%
OSWorld—66.3%
BALROG—43.5%
Vending-Bench 2—4,967

Reasoning Claude Opus 4.5 leads

Claude Opus 4: 27.3 (#121), Claude Opus 4.5: 42.6 (#51)

BenchmarkClaude Opus 4Claude Opus 4.5
ARC-AGI-28.6%37.6%
SimpleBench58.8%62%
Kagi LLM Benchmark74.3%80.2%
ARC-AGI-135.7%80%
EnigmaEval5.6%11.9%
LMArena Hard Prompts13991476
DTBench81.6%89.9%
LMCA37.4%44.5%
Epoch Capabilities Index142.67150.09
ForecastBench61.160.7
NYT Connections (extended)—52.5%
CritPt0.3%—
Chess Puzzles—12%
EBR-Bench—14.3%
Mystery Game Puzzles—22%

Math Claude Opus 4 leads

Claude Opus 4: 42.0 (#86), Claude Opus 4.5: 38.6 (#132)

BenchmarkClaude Opus 4Claude Opus 4.5
OTIS Mock AIME 2024-202564.4%86.1%
LMArena Math13901463
FrontierMath (Feb 2025 set)4.5%20.7%
FrontierMath Tier 4 (v1)4.2%4.2%
FrontierMath (Tiers 1-3)—34.4%
FrontierMath Tier 4—4.9%
ProofBench—36%
Omni-MATH61.6%—
MATH Level 585%—

Knowledge Claude Opus 4.5 leads

Claude Opus 4: 44.0 (#88), Claude Opus 4.5: 56.5 (#44)

BenchmarkClaude Opus 4Claude Opus 4.5
GPQA Diamond76.3%86%
Humanity's Last Exam10.7%25.2%
Vectara Hallucination Rate12%10.9%
LMArena Expert13861487
SimpleQA Verified—45.7%
MMLU-Pro87.5%—
Confabulations15.9%—
GPQA (HELM)70.8%—

Multimodal Too close to call

Claude Opus 4: 31.5 (#106), Claude Opus 4.5: 31.4 (#107)

BenchmarkClaude Opus 4Claude Opus 4.5
GeoBench49%75%
VPCT38%40%
LMArena Vision1192—
Furniture Assembly—28.3%
LMArena Document—1462

Multilingual Claude Opus 4.5 leads

Claude Opus 4: 48.8 (#138), Claude Opus 4.5: 54.3 (#47)

BenchmarkClaude Opus 4Claude Opus 4.5
LMArena Non-English13621438
LMArena Chinese13861470
LMArena French13721471
LMArena German13911449
LMArena Japanese13311416
LMArena Korean13211424
LMArena Russian13921447
LMArena Spanish13891458

Instruction Following Too close to call

Claude Opus 4: 77.1 (#28), Claude Opus 4.5: 77.5 (#19)

BenchmarkClaude Opus 4Claude Opus 4.5
LMArena Instruction Following14061478
IFEval91.8%—

Long Context Claude Opus 4.5 leads

Claude Opus 4: 39.6 (#172), Claude Opus 4.5: 46.5 (#22)

BenchmarkClaude Opus 4Claude Opus 4.5
LMArena Longer Query14221480
Fiction.LiveBench61.1%—
CL-bench—21.1%

Writing & Preference Claude Opus 4.5 leads

Claude Opus 4: 61.2 (#89), Claude Opus 4.5: 68.1 (#28)

BenchmarkClaude Opus 4Claude Opus 4.5
LMArena Text13771451
LMArena Creative Writing13871445
EQ-Bench Creative Writing15801687
LMArena Multi-Turn13961466
Short-Story Creative Writing83.6%—
WildBench85.2%—

Frequently asked questions

Is Claude Opus 4 better than Claude Opus 4.5?

Claude Opus 4.5 is the stronger model overall, scoring 50.5 to 43.1 on the Noometry Index.

Which is cheaper, Claude Opus 4 or Claude Opus 4.5?

Claude Opus 4.5 is cheaper. It lists at $5 per million input tokens and $25 per million output tokens; Claude Opus 4 lists at $15 and $75.

Is Claude Opus 4 or Claude Opus 4.5 better for coding?

Claude Opus 4.5 scores higher on coding benchmarks: 54.8 versus 47.2 in the Noometry coding category.

Which has the bigger context window?

Both accept 200K tokens.

How many benchmarks do Claude Opus 4 and Claude Opus 4.5 share?

44 benchmarks have published results for both models. Claude Opus 4 has 56 scored results on Noometry and Claude Opus 4.5 has 69.

Related comparisons

Go deeper