# Claude Opus 5.5 vs Claude Sonnet 5

> Side-by-side benchmark comparison for Claude Opus 5.5 and Claude Sonnet 5 across agentic, coding, multimodal, knowledge, reasoning, multilingual, and math tasks.

- Canonical page: https://benchlm.ai/compare/claude-opus-5-5-vs-claude-sonnet-5
- Last updated: September 22, 2026

- Shared sourced benchmarks: 7
- HTML indexing: indexable
- Ranking lane: BenchAlign v5

## Quick Verdict

Pick Claude Opus 5.5 if you want the stronger benchmark profile. Claude Sonnet 5 only makes more sense when its price, context window, or workload-specific category wins matter more than the overall score.

## Summary

- Claude Opus 5.5 leads overall 81.03 to 69.47.
- The clearest category separation is in agentic, where the averages are 82.9 for Claude Opus 5.5 and 66.2 for Claude Sonnet 5.
- The biggest single benchmark swing is SWE Multimodal in Coding, with scores of 61.4% and 28.1%.
- Claude Sonnet 5 is the cheaper option on output tokens, which matters if you expect large responses or heavy interactive use.

## Model Snapshot

| Property | Claude Opus 5.5 | Claude Sonnet 5 |
|----------|----------|----------|
| Creator | Anthropic | Anthropic |
| Type | Proprietary | Proprietary |
| Reasoning | Reasoning | Reasoning |
| Context | 1M | 1M |
| Overall Score | 81.03 | 69.47 |
| Benchmarks Covered | 47 | 26 |
| Pricing (input/output) | $4.00 / $20.00 | $2.00 / $10.00 |

## Category Breakdown

### Agentic

- Winner: Claude Opus 5.5
- Claude Opus 5.5 public-lane score: 82.9 (Supported · #1/157)
- Claude Sonnet 5 public-lane score: 66.2 (Supported · #13/157)

| Benchmark | Claude Opus 5.5 | Claude Sonnet 5 | Winner |
|-----------|-----------|-----------|--------|
| Terminal-Bench 4.0 | 66.40% | Coming soon | Coming soon |
| Terminal-Bench-Science 0.1 | 58.7% | Coming soon | Coming soon |
| AutomationBench | 40.0% | Coming soon | Coming soon |
| HLE w/ tools | 67.7% | 57.4% | Claude Opus 5.5 |
| OSWorld 2.0 | 48.7% | Coming soon | Coming soon |
| LAB all-pass (Harvey held-out) | 8.3% | Coming soon | Coming soon |
| LAB criterion-pass (Harvey held-out) | 91.2% | Coming soon | Coming soon |
| Toolathlon-Verified | 77.8% | Coming soon | Coming soon |
| Toolathlon Verified Pass@3 | 82.4% | Coming soon | Coming soon |
| Toolathlon Verified Pass³ | 72.2% | Coming soon | Coming soon |
| Toolathlon Verified avg. turns | 26.9 turns | Coming soon | Coming soon |
| Terminal-Bench 3.0 | Coming soon | 14.6% | Coming soon |
| Terminal-Bench 2.0 | Coming soon | 80.4% | Coming soon |
| BrowseComp | Coming soon | 84.7% | Coming soon |
| OSWorld-Verified | Coming soon | 81.2% | Coming soon |
| Terminal-Bench 2.1 (Vals) | Coming soon | 74.5% | Coming soon |
| ApprenticeBench | Coming soon | 16% | Coming soon |

### Coding

- Winner: Claude Opus 5.5
- Claude Opus 5.5 public-lane score: 80.1 (Supported · #2/159)
- Claude Sonnet 5 public-lane score: 64 (Supported · #16/159)

| Benchmark | Claude Opus 5.5 | Claude Sonnet 5 | Winner |
|-----------|-----------|-----------|--------|
| FrontierCode 1.1 Main | 54.4% | 42.7% | Claude Opus 5.5 |
| cursorBench40 | 57.8% | 34.1% | Claude Opus 5.5 |
| SWE-bench Pro | 89.9% | 63.2% | Claude Opus 5.5 |
| SWE Multilingual | 93.9% | 78.3% | Claude Opus 5.5 |
| SWE Multimodal | 61.4% | 28.1% | Claude Opus 5.5 |
| DeepSWE | 74.2% | Coming soon | Coming soon |
| FrontierCode 1.1 Extended | 63.6% | Coming soon | Coming soon |
| FrontierSWE v2 | 62.3% | Coming soon | Coming soon |
| ProgramBench | 91.2% | Coming soon | Coming soon |
| SWE-bench Verified | Coming soon | 85.2% | Coming soon |
| Terminal-Bench 2.0 | Coming soon | 80.4% | Coming soon |
| cursorBench32 | Coming soon | 61.5% | Coming soon |
| VulcanBench CII v1 | Coming soon | 89.2% | Coming soon |
| LiveCodeBench (Vals) | Coming soon | 82.4% | Coming soon |
| SWE-bench (Vals) | Coming soon | 79.6% | Coming soon |

### Reasoning

- Winner: Coming soon
- Claude Opus 5.5 public-lane score: 78.5 (#4/17)
- Claude Sonnet 5 public-lane score: 77.4 (Unranked · 2 rankable rows)

### Multimodal & Grounded

- Winner: Coming soon
- Claude Opus 5.5 public-lane score: 88.8 (#3/50)
- Claude Sonnet 5 public-lane score: 77.4 (#15/50)

| Benchmark | Claude Opus 5.5 | Claude Sonnet 5 | Winner |
|-----------|-----------|-----------|--------|
| Chartography (tools) | 89.0% | Coming soon | Coming soon |
| Chartography (no tools) | 64.4% | Coming soon | Coming soon |
| BenchCAD Vision2Code (no tools) | 0.730 | Coming soon | Coming soon |
| BenchCAD Vision2Code (tools) | 0.962 | Coming soon | Coming soon |
| Biomedical image analysis | 71.4% | Coming soon | Coming soon |
| OfficeQA | 78.9% | Coming soon | Coming soon |
| OfficeQA Pro | 67.7% | Coming soon | Coming soon |
| CharXiv | Coming soon | 88.3% | Coming soon |
| CharXiv w/o tools | Coming soon | 77% | Coming soon |

### Knowledge

- Winner: Coming soon
- Claude Opus 5.5 public-lane score: 81.8 (Estimated · #4/189)
- Claude Sonnet 5 public-lane score: 66.4 (Supported · #23/189)

| Benchmark | Claude Opus 5.5 | Claude Sonnet 5 | Winner |
|-----------|-----------|-----------|--------|
| HLE w/o tools | 64.4% | 43.2% | Claude Opus 5.5 |
| HealthBench (raw) | 68.1% | Coming soon | Coming soon |
| HealthBench (length-adjusted) | 60.6% | Coming soon | Coming soon |
| HealthBench Professional | 65.6% | Coming soon | Coming soon |
| HealthBench Professional (raw) | 77.1% | Coming soon | Coming soon |
| BioMysteryBench (human-solvable) | 89.3% | Coming soon | Coming soon |
| BioMysteryBench (human-difficult) | 50.0% | Coming soon | Coming soon |
| SpatialBench Verified | 72.0% | Coming soon | Coming soon |
| SingleCellBench | 61.2% | Coming soon | Coming soon |
| Morphology-to-molecule matching | 34.0% | Coming soon | Coming soon |
| Medicinal chemistry | 63.5% | Coming soon | Coming soon |
| Protein Design | 60.2% | Coming soon | Coming soon |
| Protein Design library ranking | 56.0% | Coming soon | Coming soon |
| De novo protein-binder design | 82.6% | Coming soon | Coming soon |
| Protocols (troubleshooting) | 73.7% | Coming soon | Coming soon |
| Protocols (understanding) | 69.0% | Coming soon | Coming soon |
| HLE | Coming soon | 57.4% | Coming soon |
| HLE-Verified | Coming soon | 31.0% | Coming soon |
| LABBench2 | Coming soon | 80.1% | Coming soon |
| GPQA Diamond (Vals) | Coming soon | 88.9% | Coming soon |
| MMLU-Pro (Vals) | Coming soon | 87.5% | Coming soon |

### Multilingual

- Winner: Coming soon
- Claude Opus 5.5 public-lane score: Coming soon
- Claude Sonnet 5 public-lane score: Coming soon

| Benchmark | Claude Opus 5.5 | Claude Sonnet 5 | Winner |
|-----------|-----------|-----------|--------|
| GMMLU | 94.3% | Coming soon | Coming soon |
| MILU | 93.1% | Coming soon | Coming soon |

### Mathematics

- Winner: Coming soon
- Claude Opus 5.5 public-lane score: Coming soon
- Claude Sonnet 5 public-lane score: Coming soon

| Benchmark | Claude Opus 5.5 | Claude Sonnet 5 | Winner |
|-----------|-----------|-----------|--------|
| ArXivMath Aug. 2026 (no tools) | 91.2% | Coming soon | Coming soon |
| ArXivMath Aug. 2026 (tools) | 96.9% | Coming soon | Coming soon |

## FAQ

### Which is better overall, Claude Opus 5.5 or Claude Sonnet 5?

Claude Opus 5.5 is ahead overall on BenchLM right now.

### Where is the biggest gap between Claude Opus 5.5 and Claude Sonnet 5?

The widest category gap is in agentic, where the averages are 82.9 for Claude Opus 5.5 and 66.2 for Claude Sonnet 5.

### How many benchmarks does Claude Opus 5.5 cover on BenchLM?

Claude Opus 5.5 currently has 47 sourced benchmark scores on BenchLM.

### How many benchmarks does Claude Sonnet 5 cover on BenchLM?

Claude Sonnet 5 currently has 26 sourced benchmark scores on BenchLM.

## Related Comparisons

- [Claude Opus 5.5 vs Claude Fable 5.1](/compare/claude-fable-5-1-vs-claude-opus-5-5)
- [Claude Sonnet 5 vs Claude Fable 5.1](/compare/claude-fable-5-1-vs-claude-sonnet-5)
- [Claude Opus 5.5 vs GPT-6 Astra](/compare/claude-opus-5-5-vs-gpt-6-astra)
- [Claude Sonnet 5 vs GPT-6 Astra](/compare/claude-sonnet-5-vs-gpt-6-astra)

## Explore More

- [Claude Opus 5.5 profile](/models/claude-opus-5-5)
- [Claude Sonnet 5 profile](/models/claude-sonnet-5)
- [Compare Pricing](/llm-pricing)
- [Alternative Finder](/tools/alternative-finder)
- [LLM Selector](/tools/llm-selector)
- [Overall Rankings](/best/overall)