# Claude 2 vs Claude Sonnet 5.5

> Claude Sonnet 5.5 is the stronger model overall, scoring 61.9 to 25.0 on the Noometry Index.

- Canonical page: https://noometry.com/compare/claude-2-vs-claude-sonnet-5-5
- Last updated: 2026-10-10
- Shared benchmarks: 3

## Summary

- They share 3 benchmarks with published results for both. Claude 2 scores higher in 0 categories and Claude Sonnet 5.5 in 3 categories; 3 gaps are clear of the uncertainty.
- The widest gap is in math, where Claude Sonnet 5.5 leads 87.9 to 9.3.
- The biggest single-benchmark swing is OTIS Mock AIME 2024-2025: 2.5% for Claude 2 and 100% for Claude Sonnet 5.5.

## Snapshot

| | Claude 2 | Claude Sonnet 5.5 |
|---|---|---|
| Provider | Anthropic | Anthropic |
| Noometry Index | 25.0 | 61.9 |
| Rank | 346 | 10 |
| Context | — | 1M |
| Input $/M | — | $2 |
| Output $/M | — | $10 |
| Weights | Proprietary | Proprietary |

## Coding

- Claude 2: —
- Claude Sonnet 5.5: 67.3 (#6)

| Benchmark | Claude 2 | Claude Sonnet 5.5 |
|---|---|---|
| FrontierCode | — | 52.1% |
| CursorBench | — | 55.5% |
| LMArena WebDev | — | 1774 |
| FrontierSWE | — | 61.9% |
| SciCode | — | 61% |
| LMArena Coding | — | 1513 |
| ALE-Bench | — | 1,819 |
| HumanEval+ | 61.6% | — |

## Agentic & Tool Use

- Claude 2: —
- Claude Sonnet 5.5: 45.0 (#16)

| Benchmark | Claude 2 | Claude Sonnet 5.5 |
|---|---|---|
| APEX-Agents | — | 75.5% |

## Reasoning

- Claude 2: 21.7 (#216)
- Claude Sonnet 5.5: 54.0 (#28)

| Benchmark | Claude 2 | Claude Sonnet 5.5 |
|---|---|---|
| Epoch Capabilities Index | 120.13 | 165.03 |
| NYT Connections (extended) | — | 80.5% |
| CritPt | — | 31.4% |
| LMArena Hard Prompts | — | 1495 |
| Mystery Game Puzzles | — | 65% |
| DTBench | 51.9% | — |

## Math

- Claude 2: 9.3 (#320)
- Claude Sonnet 5.5: 87.9 (#6)

| Benchmark | Claude 2 | Claude Sonnet 5.5 |
|---|---|---|
| OTIS Mock AIME 2024-2025 | 2.5% | 100% |
| FrontierMath (Tiers 1-3) | — | 88.8% |
| FrontierMath Tier 4 | — | 80.5% |
| ProofBench | — | 100% |
| LMArena Math | — | 1510 |
| MATH Level 5 | 11.7% | — |
| FrontierMath Erdős | — | 2.9% |

## Knowledge

- Claude 2: 16.9 (#287)
- Claude Sonnet 5.5: 66.0 (#12)

| Benchmark | Claude 2 | Claude Sonnet 5.5 |
|---|---|---|
| GPQA Diamond | 34.7% | 95.6% |
| SimpleQA Verified | — | 46.5% |
| LMArena Expert | — | 1540 |
| MMLU | 78.5% | — |
| TriviaQA | 87.5% | — |

## Multimodal

- Claude 2: —
- Claude Sonnet 5.5: 51.5 (#6)

| Benchmark | Claude 2 | Claude Sonnet 5.5 |
|---|---|---|
| LMArena Vision | — | 1289 |
| Furniture Assembly | — | 75% |

## Multilingual

- Claude 2: —
- Claude Sonnet 5.5: 55.3 (#30)

| Benchmark | Claude 2 | Claude Sonnet 5.5 |
|---|---|---|
| LMArena Non-English | — | 1452 |
| LMArena Chinese | — | 1522 |
| LMArena Russian | — | 1451 |

## Instruction Following

- Claude 2: —
- Claude Sonnet 5.5: 78.3 (#11)

| Benchmark | Claude 2 | Claude Sonnet 5.5 |
|---|---|---|
| LMArena Instruction Following | — | 1495 |

## Long Context

- Claude 2: —
- Claude Sonnet 5.5: 45.9 (#28)

| Benchmark | Claude 2 | Claude Sonnet 5.5 |
|---|---|---|
| LMArena Longer Query | — | 1498 |

## Writing & Preference

- Claude 2: —
- Claude Sonnet 5.5: 66.0 (#40)

| Benchmark | Claude 2 | Claude Sonnet 5.5 |
|---|---|---|
| LMArena Text | — | 1471 |
| LMArena Creative Writing | — | 1465 |
| LMArena Multi-Turn | — | 1474 |

## FAQ

### Is Claude 2 better than Claude Sonnet 5.5?

Claude Sonnet 5.5 is the stronger model overall, scoring 61.9 to 25.0 on the Noometry Index.

### How many benchmarks do Claude 2 and Claude Sonnet 5.5 share?

3 benchmarks have published results for both models. Claude 2 has 8 scored results on Noometry and Claude Sonnet 5.5 has 32.