# Claude Sonnet 5.5 vs Yi-Lightning

> Claude Sonnet 5.5 is the stronger model overall, scoring 61.9 to 37.1 on the Noometry Index.

- Canonical page: https://noometry.com/compare/claude-sonnet-5-5-vs-yi-lightning
- Last updated: 2026-10-10
- Shared benchmarks: 12

## Summary

- They share 12 benchmarks with published results for both. Claude Sonnet 5.5 scores higher in 8 categories and Yi-Lightning in 0 categories; 8 gaps are clear of the uncertainty.
- The widest gap is in math, where Claude Sonnet 5.5 leads 87.9 to 36.2.

## Snapshot

| | Claude Sonnet 5.5 | Yi-Lightning |
|---|---|---|
| Provider | Anthropic | 01.AI |
| Noometry Index | 61.9 | 37.1 |
| Rank | 10 | 209 |
| Context | 1M | — |
| Input $/M | $2 | — |
| Output $/M | $10 | — |
| Weights | Proprietary | Proprietary |

## Coding

- Claude Sonnet 5.5: 67.3 (#6)
- Yi-Lightning: 27.4 (#320)

| Benchmark | Claude Sonnet 5.5 | Yi-Lightning |
|---|---|---|
| LMArena Coding | 1513 | 1312 |
| FrontierCode | 52.1% | — |
| Aider Polyglot | — | 12.9% |
| CursorBench | 55.5% | — |
| LMArena WebDev | 1774 | — |
| FrontierSWE | 61.9% | — |
| SciCode | 61% | — |
| ALE-Bench | 1,819 | — |

## Agentic & Tool Use

- Claude Sonnet 5.5: 45.0 (#16)
- Yi-Lightning: —

| Benchmark | Claude Sonnet 5.5 | Yi-Lightning |
|---|---|---|
| APEX-Agents | 75.5% | — |

## Reasoning

- Claude Sonnet 5.5: 54.0 (#28)
- Yi-Lightning: 25.9 (#139)

| Benchmark | Claude Sonnet 5.5 | Yi-Lightning |
|---|---|---|
| LMArena Hard Prompts | 1495 | 1302 |
| NYT Connections (extended) | 80.5% | — |
| CritPt | 31.4% | — |
| Mystery Game Puzzles | 65% | — |
| Epoch Capabilities Index | 165.03 | — |

## Math

- Claude Sonnet 5.5: 87.9 (#6)
- Yi-Lightning: 36.2 (#172)

| Benchmark | Claude Sonnet 5.5 | Yi-Lightning |
|---|---|---|
| LMArena Math | 1510 | 1300 |
| FrontierMath (Tiers 1-3) | 88.8% | — |
| FrontierMath Tier 4 | 80.5% | — |
| OTIS Mock AIME 2024-2025 | 100% | — |
| ProofBench | 100% | — |
| FrontierMath Erdős | 2.9% | — |

## Knowledge

- Claude Sonnet 5.5: 66.0 (#12)
- Yi-Lightning: 35.4 (#185)

| Benchmark | Claude Sonnet 5.5 | Yi-Lightning |
|---|---|---|
| LMArena Expert | 1540 | 1286 |
| GPQA Diamond | 95.6% | — |
| SimpleQA Verified | 46.5% | — |

## Multimodal

- Claude Sonnet 5.5: 51.5 (#6)
- Yi-Lightning: —

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

## Multilingual

- Claude Sonnet 5.5: 55.3 (#30)
- Yi-Lightning: 42.2 (#196)

| Benchmark | Claude Sonnet 5.5 | Yi-Lightning |
|---|---|---|
| LMArena Non-English | 1452 | 1269 |
| LMArena Chinese | 1522 | 1320 |
| LMArena Russian | 1451 | 1255 |
| LMArena French | — | 1305 |
| LMArena German | — | 1267 |
| LMArena Japanese | — | 1228 |
| LMArena Korean | — | 1192 |
| LMArena Spanish | — | 1315 |

## Instruction Following

- Claude Sonnet 5.5: 78.3 (#11)
- Yi-Lightning: 67.4 (#196)

| Benchmark | Claude Sonnet 5.5 | Yi-Lightning |
|---|---|---|
| LMArena Instruction Following | 1495 | 1278 |

## Long Context

- Claude Sonnet 5.5: 45.9 (#28)
- Yi-Lightning: 39.4 (#181)

| Benchmark | Claude Sonnet 5.5 | Yi-Lightning |
|---|---|---|
| LMArena Longer Query | 1498 | 1297 |

## Writing & Preference

- Claude Sonnet 5.5: 66.0 (#40)
- Yi-Lightning: 50.2 (#184)

| Benchmark | Claude Sonnet 5.5 | Yi-Lightning |
|---|---|---|
| LMArena Text | 1471 | 1302 |
| LMArena Creative Writing | 1465 | 1280 |
| LMArena Multi-Turn | 1474 | 1311 |

## FAQ

### Is Claude Sonnet 5.5 better than Yi-Lightning?

Claude Sonnet 5.5 is the stronger model overall, scoring 61.9 to 37.1 on the Noometry Index.

### Is Claude Sonnet 5.5 or Yi-Lightning better for coding?

Claude Sonnet 5.5 scores higher on coding benchmarks: 67.3 versus 27.4 in the Noometry coding category.

### How many benchmarks do Claude Sonnet 5.5 and Yi-Lightning share?

12 benchmarks have published results for both models. Claude Sonnet 5.5 has 32 scored results on Noometry and Yi-Lightning has 18.