# Claude Opus 5.5 vs Solar Open 2

> Side-by-side benchmark comparison for Claude Opus 5.5 and Solar Open 2 across agentic, coding, multimodal, knowledge, reasoning, multilingual, and math tasks.

- Canonical page: https://benchlm.ai/compare/claude-opus-5-5-vs-solar-open-2
- Last updated: September 22, 2026

- Shared sourced benchmarks: 1
- HTML indexing: indexable
- Ranking lane: BenchAlign v5

## Quick Verdict

Evidence is too thin for a benchmark verdict: Claude Opus 5.5 and Solar Open 2 share only 1 sourced benchmark row.

## Summary

- Only 1 shared sourced benchmark row is available. That is not enough for a broad capability verdict, so this mirror does not name an overall winner.
- Solar Open 2 has the lower published output-token price.

## Model Snapshot

| Property | Claude Opus 5.5 | Solar Open 2 |
|----------|----------|----------|
| Creator | Anthropic | Upstage |
| Type | Proprietary | Open Weight |
| Reasoning | Reasoning | Reasoning |
| Context | 1M | 1M |
| Independent public score (not head-to-head) | 81.03 | null |
| Benchmarks Covered | 47 | 11 |
| Pricing (input/output) | $4.00 / $20.00 | $0.00 / $0.00 |

## Category Breakdown

### Agentic

- Winner: Insufficient shared evidence
- Claude Opus 5.5 public-lane score: 82.9 (Supported · #1/157)
- Solar Open 2 public-lane score: Coming soon

| Benchmark | Claude Opus 5.5 | Solar Open 2 | 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% | Coming soon | Coming soon |
| 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 |
| terminalBenchHard | Coming soon | 28.3% | Coming soon |
| APEX-Agents | Coming soon | 16.6% | Coming soon |
| MCP Atlas | Coming soon | 58.2% | Coming soon |

### Coding

- Winner: Insufficient shared evidence
- Claude Opus 5.5 public-lane score: 80.1 (Supported · #2/159)
- Solar Open 2 public-lane score: Coming soon

| Benchmark | Claude Opus 5.5 | Solar Open 2 | Winner |
|-----------|-----------|-----------|--------|
| FrontierCode 1.1 Main | 54.4% | Coming soon | Coming soon |
| cursorBench40 | 57.8% | Coming soon | Coming soon |
| SWE-bench Pro | 89.9% | Coming soon | Coming soon |
| SWE Multilingual | 93.9% | Coming soon | Coming soon |
| SWE Multimodal | 61.4% | Coming soon | Coming soon |
| 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 |
| LiveCodeBench v6 | Coming soon | 92.4% | Coming soon |
| SWE-bench Verified | Coming soon | 70.4% | Coming soon |

### Reasoning

- Winner: Insufficient shared evidence
- Claude Opus 5.5 public-lane score: 78.5 (#4/17)
- Solar Open 2 public-lane score: Coming soon

### Multimodal & Grounded

- Winner: Insufficient shared evidence
- Claude Opus 5.5 public-lane score: 88.8 (#3/50)
- Solar Open 2 public-lane score: Coming soon

| Benchmark | Claude Opus 5.5 | Solar Open 2 | 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 |

### Knowledge

- Winner: Insufficient shared evidence
- Claude Opus 5.5 public-lane score: 81.8 (Estimated · #4/189)
- Solar Open 2 public-lane score: Coming soon

| Benchmark | Claude Opus 5.5 | Solar Open 2 | Winner |
|-----------|-----------|-----------|--------|
| HLE w/o tools | 64.4% | 28.8% | 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 |
| MMLU-Pro | Coming soon | 86.2% | Coming soon |
| GPQA-D | Coming soon | 86.3% | Coming soon |

### Multilingual

- Winner: Insufficient shared evidence
- Claude Opus 5.5 public-lane score: Coming soon
- Solar Open 2 public-lane score: Coming soon

| Benchmark | Claude Opus 5.5 | Solar Open 2 | Winner |
|-----------|-----------|-----------|--------|
| GMMLU | 94.3% | Coming soon | Coming soon |
| MILU | 93.1% | Coming soon | Coming soon |

### Instruction Following

- Winner: Insufficient shared evidence
- Claude Opus 5.5 public-lane score: Coming soon
- Solar Open 2 public-lane score: Coming soon

| Benchmark | Claude Opus 5.5 | Solar Open 2 | Winner |
|-----------|-----------|-----------|--------|
| IFBench | Coming soon | 80% | Coming soon |

### Mathematics

- Winner: Insufficient shared evidence
- Claude Opus 5.5 public-lane score: Coming soon
- Solar Open 2 public-lane score: Coming soon

| Benchmark | Claude Opus 5.5 | Solar Open 2 | Winner |
|-----------|-----------|-----------|--------|
| ArXivMath Aug. 2026 (no tools) | 91.2% | Coming soon | Coming soon |
| ArXivMath Aug. 2026 (tools) | 96.9% | Coming soon | Coming soon |
| HMMT Feb 2026 | Coming soon | 93.9% | Coming soon |
| AIME26 | Coming soon | 95.7% | Coming soon |

## FAQ

### Is there enough evidence to pick between Claude Opus 5.5 and Solar Open 2?

Not yet. The models share only 1 sourced benchmark row, so this mirror reports the available measurements and metadata without naming a broad winner.

### What can I compare safely on this page?

Published pricing, context windows, model type, and individual shared benchmark rows are directly comparable. Independent overall scores and non-overlapping benchmark coverage are labeled separately and should not be read as a controlled head-to-head result.

## Related Comparisons

- [Claude Opus 5.5 vs Claude Fable 5.1](/compare/claude-fable-5-1-vs-claude-opus-5-5)
- [Solar Open 2 vs Claude Fable 5.1](/compare/claude-fable-5-1-vs-solar-open-2)
- [Claude Opus 5.5 vs GPT-6 Astra](/compare/claude-opus-5-5-vs-gpt-6-astra)
- [Solar Open 2 vs GPT-6 Astra](/compare/gpt-6-astra-vs-solar-open-2)

## Explore More

- [Claude Opus 5.5 profile](/models/claude-opus-5-5)
- [Solar Open 2 profile](/models/solar-open-2)
- [Compare Pricing](/llm-pricing)
- [Alternative Finder](/tools/alternative-finder)
- [LLM Selector](/tools/llm-selector)
- [Overall Rankings](/best/overall)