Noometry

Model comparison

Claude 2.1 vs Claude Opus 4

Claude Opus 4 is the stronger model overall, scoring 43.1 to 25.2 on the Noometry Index.

Last verified . 6 shared benchmarks.

Claude 2.1 Anthropic

25.2

Rank #345 Reported

Claude Opus 4 Anthropic

43.1

Rank #100 Confirmed

Summary

  • They share 6 benchmarks with published results for both. Claude 2.1 scores higher in 0 categories and Claude Opus 4 in 4 categories; 4 gaps are clear of the uncertainty.
  • The widest gap is in math, where Claude Opus 4 leads 42.0 to 10.2.
  • The biggest single-benchmark swing is OTIS Mock AIME 2024-2025: 1.9% for Claude 2.1 and 64.4% for Claude Opus 4.

Side by side

Claude 2.1Claude Opus 4
ProviderAnthropicAnthropic
Noometry Index25.243.1
Released2023-11-212025-05-22
WeightsProprietaryProprietary
Context window—200K
Max output—32K
Input $ / M tokens—$15
Output $ / M tokens—$75
Results tracked756

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Category by category

Coding Claude Opus 4 leads

Claude 2.1: 26.2 (#327), Claude Opus 4: 47.2 (#62)

BenchmarkClaude 2.1Claude Opus 4
WeirdML7.1%43.7%
SWE-bench Verified—70.7%
SWE-bench Verified (bash only)—67.6%
Aider Polyglot—72%
GSO—6.9%
LMArena Coding—1442
AlgoTune—1.33

Agentic & Tool Use Not comparable

Claude 2.1: —, Claude Opus 4: 34.8 (#42)

BenchmarkClaude 2.1Claude Opus 4
Cybench—38%
DeepResearch Bench—46.8%
LMArena Search—1127
METR Time Horizons—63.9%

Reasoning Claude Opus 4 leads

Claude 2.1: 21.4 (#221), Claude Opus 4: 27.3 (#121)

BenchmarkClaude 2.1Claude Opus 4
DTBench51%81.6%
Epoch Capabilities Index119.27142.67
ForecastBench54.261.1
ARC-AGI-2—8.6%
SimpleBench—58.8%
Kagi LLM Benchmark—74.3%
ARC-AGI-1—35.7%
CritPt—0.3%
EnigmaEval—5.6%
LMArena Hard Prompts—1399
LMCA—37.4%

Math Claude Opus 4 leads

Claude 2.1: 10.2 (#315), Claude Opus 4: 42.0 (#86)

BenchmarkClaude 2.1Claude Opus 4
OTIS Mock AIME 2024-20251.9%64.4%
Omni-MATH—61.6%
LMArena Math—1390
MATH Level 5—85%
FrontierMath (Feb 2025 set)—4.5%
FrontierMath Tier 4 (v1)—4.2%

Knowledge Claude Opus 4 leads

Claude 2.1: 15.4 (#292), Claude Opus 4: 44.0 (#88)

BenchmarkClaude 2.1Claude Opus 4
GPQA Diamond33%76.3%
Humanity's Last Exam—10.7%
MMLU-Pro—87.5%
Confabulations—15.9%
Vectara Hallucination Rate—12%
GPQA (HELM)—70.8%
LMArena Expert—1386
MMLU73.5%—

Multimodal Not comparable

Claude 2.1: —, Claude Opus 4: 31.5 (#106)

BenchmarkClaude 2.1Claude Opus 4
LMArena Vision—1192
GeoBench—49%
VPCT—38%

Multilingual Not comparable

Claude 2.1: —, Claude Opus 4: 48.8 (#138)

BenchmarkClaude 2.1Claude Opus 4
LMArena Non-English—1362
LMArena Chinese—1386
LMArena French—1372
LMArena German—1391
LMArena Japanese—1331
LMArena Korean—1321
LMArena Russian—1392
LMArena Spanish—1389

Instruction Following Not comparable

Claude 2.1: —, Claude Opus 4: 77.1 (#28)

BenchmarkClaude 2.1Claude Opus 4
IFEval—91.8%
LMArena Instruction Following—1406

Long Context Not comparable

Claude 2.1: —, Claude Opus 4: 39.6 (#172)

BenchmarkClaude 2.1Claude Opus 4
Fiction.LiveBench—61.1%
LMArena Longer Query—1422

Writing & Preference Not comparable

Claude 2.1: —, Claude Opus 4: 61.2 (#89)

BenchmarkClaude 2.1Claude Opus 4
LMArena Text—1377
LMArena Creative Writing—1387
Short-Story Creative Writing—83.6%
EQ-Bench Creative Writing—1580
WildBench—85.2%
LMArena Multi-Turn—1396

Frequently asked questions

Is Claude 2.1 better than Claude Opus 4?

Claude Opus 4 is the stronger model overall, scoring 43.1 to 25.2 on the Noometry Index.

Is Claude 2.1 or Claude Opus 4 better for coding?

Claude Opus 4 scores higher on coding benchmarks: 47.2 versus 26.2 in the Noometry coding category.

How many benchmarks do Claude 2.1 and Claude Opus 4 share?

6 benchmarks have published results for both models. Claude 2.1 has 7 scored results on Noometry and Claude Opus 4 has 56.

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