# Claude Sonnet 5.5 vs Sonar

> Claude Sonnet 5.5 is the stronger model overall, scoring 61.9 to 38.5 on the Noometry Index. Sonar costs 4.0× less per token, which makes it the better buy when Claude Sonnet 5.5's lead doesn't matter for your workload.

- Canonical page: https://noometry.com/compare/claude-sonnet-5-5-vs-sonar
- Last updated: 2026-10-11
- Shared benchmarks: 0

## Summary

- The widest gap is in math, where Claude Sonnet 5.5 leads 87.9 to 33.7.
- Sonar is cheaper at $1 / $1 per million input/output tokens, against $2 / $10 for Claude Sonnet 5.5.
- Claude Sonnet 5.5 accepts more context: 1M tokens versus 128K.

## Snapshot

| | Claude Sonnet 5.5 | Sonar |
|---|---|---|
| Provider | Anthropic | Perplexity |
| Noometry Index | 61.9 | 38.5 |
| Rank | 10 | 187 |
| Context | 1M | 128K |
| Input $/M | $2 | $1 |
| Output $/M | $10 | $1 |
| Weights | Proprietary | Proprietary |

## Coding

- Claude Sonnet 5.5: 67.3 (#6)
- Sonar: 35.7 (#221)

| Benchmark | Claude Sonnet 5.5 | Sonar |
|---|---|---|
| FrontierCode | 52.1% | — |
| CursorBench | 55.5% | — |
| LMArena WebDev | 1774 | — |
| FrontierSWE | 61.9% | — |
| SciCode | 61% | — |
| LiveBench Coding | — | 35.1% |
| LMArena Coding | 1513 | — |
| ALE-Bench | 1,819 | — |

## Agentic & Tool Use

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

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

## Reasoning

- Claude Sonnet 5.5: 54.0 (#28)
- Sonar: 21.1 (#227)

| Benchmark | Claude Sonnet 5.5 | Sonar |
|---|---|---|
| NYT Connections (extended) | 80.5% | — |
| CritPt | 31.4% | — |
| LiveBench Reasoning | — | 46.3% |
| LMArena Hard Prompts | 1495 | — |
| Mystery Game Puzzles | 65% | — |
| LiveBench Data Analysis | — | 37.9% |
| Epoch Capabilities Index | 165.03 | — |
| LiveBench | — | 46.9% |

## Math

- Claude Sonnet 5.5: 87.9 (#6)
- Sonar: 33.7 (#200)

| Benchmark | Claude Sonnet 5.5 | Sonar |
|---|---|---|
| FrontierMath (Tiers 1-3) | 88.8% | — |
| FrontierMath Tier 4 | 80.5% | — |
| OTIS Mock AIME 2024-2025 | 100% | — |
| ProofBench | 100% | — |
| LiveBench Math | — | 41.6% |
| LMArena Math | 1510 | — |
| FrontierMath Erdős | 2.9% | — |

## Knowledge

- Claude Sonnet 5.5: 66.0 (#12)
- Sonar: —

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

## Multimodal

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

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

## Multilingual

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

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

## Instruction Following

- Claude Sonnet 5.5: 78.3 (#11)
- Sonar: 71.4 (#150)

| Benchmark | Claude Sonnet 5.5 | Sonar |
|---|---|---|
| LiveBench Instruction Following | — | 76.2% |
| LMArena Instruction Following | 1495 | — |

## Long Context

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

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

## Writing & Preference

- Claude Sonnet 5.5: 66.0 (#40)
- Sonar: 52.6 (#167)

| Benchmark | Claude Sonnet 5.5 | Sonar |
|---|---|---|
| LMArena Text | 1471 | — |
| LMArena Creative Writing | 1465 | — |
| LMArena Multi-Turn | 1474 | — |
| LiveBench Language | — | 44.1% |

## FAQ

### Is Claude Sonnet 5.5 better than Sonar?

Claude Sonnet 5.5 is the stronger model overall, scoring 61.9 to 38.5 on the Noometry Index. Sonar costs 4.0× less per token, which makes it the better buy when Claude Sonnet 5.5's lead doesn't matter for your workload.

### Which is cheaper, Claude Sonnet 5.5 or Sonar?

Sonar is cheaper. It lists at $1 per million input tokens and $1 per million output tokens; Claude Sonnet 5.5 lists at $2 and $10.

### Is Claude Sonnet 5.5 or Sonar better for coding?

Claude Sonnet 5.5 scores higher on coding benchmarks: 67.3 versus 35.7 in the Noometry coding category.

### Which has the bigger context window?

Claude Sonnet 5.5 does, with 1M tokens against 128K.

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

0 benchmarks have published results for both models. Claude Sonnet 5.5 has 32 scored results on Noometry and Sonar has 7.