# Claude 3 Sonnet vs Claude Opus 5.5

> Claude Opus 5.5 is the stronger model overall, scoring 68.5 to 28.8 on the Noometry Index.

- Canonical page: https://noometry.com/compare/claude-3-sonnet-vs-claude-opus-5-5
- Last updated: 2026-10-10
- Shared benchmarks: 14

## Summary

- They share 14 benchmarks with published results for both. Claude 3 Sonnet scores higher in 0 categories and Claude Opus 5.5 in 9 categories; 9 gaps are clear of the uncertainty.
- The widest gap is in math, where Claude Opus 5.5 leads 92.4 to 10.0.
- The biggest single-benchmark swing is OTIS Mock AIME 2024-2025: 2.5% for Claude 3 Sonnet and 100% for Claude Opus 5.5.

## Snapshot

| | Claude 3 Sonnet | Claude Opus 5.5 |
|---|---|---|
| Provider | Anthropic | Anthropic |
| Noometry Index | 28.8 | 68.5 |
| Rank | 311 | 3 |
| Context | — | 1M |
| Input $/M | — | $4 |
| Output $/M | — | $20 |
| Weights | Proprietary | Proprietary |

## Coding

- Claude 3 Sonnet: 29.2 (#296)
- Claude Opus 5.5: 71.4 (#1)

| Benchmark | Claude 3 Sonnet | Claude Opus 5.5 |
|---|---|---|
| LMArena Coding | 1223 | 1545 |
| FrontierCode | — | 54.4% |
| CursorBench | — | 57.8% |
| LMArena WebDev | — | 1820 |
| FrontierSWE | — | 62.3% |
| SciCode | — | 66.9% |
| WeirdML | 10.2% | — |
| BigCodeBench Instruct | 42.7% | — |
| MirrorCode | — | 77.4% |
| BigCodeBench Complete | 53.8% | — |
| HumanEval+ | 64% | — |
| MBPP+ | 69.3% | — |

## Agentic & Tool Use

- Claude 3 Sonnet: —
- Claude Opus 5.5: 45.3 (#13)

| Benchmark | Claude 3 Sonnet | Claude Opus 5.5 |
|---|---|---|
| APEX-Agents | — | 73.5% |
| GDP.pdf | — | 30.6% |

## Reasoning

- Claude 3 Sonnet: 19.7 (#232)
- Claude Opus 5.5: 79.5 (#2)

| Benchmark | Claude 3 Sonnet | Claude Opus 5.5 |
|---|---|---|
| LMArena Hard Prompts | 1197 | 1545 |
| DTBench | 53.6% | 98.9% |
| ARC-AGI-2 | — | 92.5% |
| NYT Connections (extended) | — | 88.5% |
| ARC-AGI-1 | — | 97.5% |
| CritPt | — | 31.7% |
| EBR-Bench | — | 71.4% |
| Mystery Game Puzzles | — | 71% |
| LMCA | — | 68.2% |
| Epoch Capabilities Index | 120.69 | — |
| WinoGrande | 75.1% | — |

## Math

- Claude 3 Sonnet: 10.0 (#305)
- Claude Opus 5.5: 92.4 (#2)

| Benchmark | Claude 3 Sonnet | Claude Opus 5.5 |
|---|---|---|
| OTIS Mock AIME 2024-2025 | 2.5% | 100% |
| FrontierMath (Tiers 1-3) | — | 91.2% |
| FrontierMath Tier 4 | — | 95% |
| ProofBench | — | 100% |
| LMArena Math | 1213 | — |
| MATH Level 5 | 18.2% | — |

## Knowledge

- Claude 3 Sonnet: 21.1 (#271)
- Claude Opus 5.5: 66.6 (#9)

| Benchmark | Claude 3 Sonnet | Claude Opus 5.5 |
|---|---|---|
| GPQA Diamond | 40.6% | 90.6% |
| LMArena Expert | 1173 | 1564 |
| SimpleQA Verified | — | 72.2% |
| MMLU | 75.9% | — |

## Multimodal

- Claude 3 Sonnet: 24.7 (#120)
- Claude Opus 5.5: 56.5 (#2)

| Benchmark | Claude 3 Sonnet | Claude Opus 5.5 |
|---|---|---|
| LMArena Vision | 984 | — |
| Furniture Assembly | — | 83.3% |

## Multilingual

- Claude 3 Sonnet: 38.0 (#229)
- Claude Opus 5.5: 59.8 (#1)

| Benchmark | Claude 3 Sonnet | Claude Opus 5.5 |
|---|---|---|
| LMArena Non-English | 1205 | 1513 |
| LMArena Chinese | 1188 | 1572 |
| LMArena Russian | 1227 | 1532 |
| LMArena French | 1228 | — |
| LMArena German | 1204 | — |
| LMArena Japanese | 1131 | — |
| LMArena Korean | 1128 | — |
| LMArena Spanish | 1204 | — |

## Instruction Following

- Claude 3 Sonnet: 63.1 (#230)
- Claude Opus 5.5: 80.1 (#2)

| Benchmark | Claude 3 Sonnet | Claude Opus 5.5 |
|---|---|---|
| LMArena Instruction Following | 1200 | 1535 |

## Long Context

- Claude 3 Sonnet: 36.7 (#223)
- Claude Opus 5.5: 47.3 (#18)

| Benchmark | Claude 3 Sonnet | Claude Opus 5.5 |
|---|---|---|
| LMArena Longer Query | 1211 | 1540 |

## Writing & Preference

- Claude 3 Sonnet: 42.3 (#233)
- Claude Opus 5.5: 78.7 (#3)

| Benchmark | Claude 3 Sonnet | Claude Opus 5.5 |
|---|---|---|
| LMArena Text | 1218 | 1518 |
| LMArena Creative Writing | 1186 | 1538 |
| LMArena Multi-Turn | 1227 | 1520 |
| EQ-Bench Creative Writing | — | 2050 |

## FAQ

### Is Claude 3 Sonnet better than Claude Opus 5.5?

Claude Opus 5.5 is the stronger model overall, scoring 68.5 to 28.8 on the Noometry Index.

### Is Claude 3 Sonnet or Claude Opus 5.5 better for coding?

Claude Opus 5.5 scores higher on coding benchmarks: 71.4 versus 29.2 in the Noometry coding category.

### How many benchmarks do Claude 3 Sonnet and Claude Opus 5.5 share?

14 benchmarks have published results for both models. Claude 3 Sonnet has 30 scored results on Noometry and Claude Opus 5.5 has 35.