# Claude Sonnet 4.5 Thinking vs Muse Spark

> Side-by-side benchmark comparison for Claude Sonnet 4.5 Thinking and Muse Spark across agentic, coding, multimodal, knowledge, reasoning, multilingual, and math tasks.

- Canonical page: https://benchlm.ai/compare/claude-sonnet-4-5-thinking-vs-muse-spark
- Last updated: September 4, 2026

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

## Quick Verdict

Evidence is too thin for a benchmark verdict: Claude Sonnet 4.5 Thinking and Muse Spark 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.
- Muse Spark has the larger published context window at 262K.

## Model Snapshot

| Property | Claude Sonnet 4.5 Thinking | Muse Spark |
|----------|----------|----------|
| Creator | Anthropic | Meta |
| Type | Proprietary | Proprietary |
| Reasoning | Reasoning | Reasoning |
| Context | 200K | 262K |
| Independent public score (not head-to-head) | null | 68.39 |
| Benchmarks Covered | 1 | 24 |
| Pricing (input/output) | N/A | N/A |

## Category Breakdown

### Agentic

- Winner: Insufficient shared evidence
- Claude Sonnet 4.5 Thinking public-lane score: Coming soon
- Muse Spark public-lane score: 58.8 (Supported · #31/151)

| Benchmark | Claude Sonnet 4.5 Thinking | Muse Spark | Winner |
|-----------|-----------|-----------|--------|
| Terminal-Bench 2.0 | Coming soon | 59% | Coming soon |
| τ²-bench results | Coming soon | 91.5% | Coming soon |
| DeepSearchQA | Coming soon | 74.8% | Coming soon |
| CyberGym | Coming soon | 43.5% | Coming soon |
| Claw-Eval | Coming soon | 63.8% | Coming soon |

### Coding

- Winner: Insufficient shared evidence
- Claude Sonnet 4.5 Thinking public-lane score: Coming soon
- Muse Spark public-lane score: 59.2 (Supported · #28/183)

| Benchmark | Claude Sonnet 4.5 Thinking | Muse Spark | Winner |
|-----------|-----------|-----------|--------|
| Vibe Code Bench | 22.62% | 19.67% | Claude Sonnet 4.5 Thinking |
| SWE-bench Verified | Coming soon | 77.4% | Coming soon |
| SWE-bench Pro | Coming soon | 52.4% | Coming soon |
| LiveCodeBench Pro | Coming soon | 80.0% | Coming soon |

### Multimodal & Grounded

- Winner: Insufficient shared evidence
- Claude Sonnet 4.5 Thinking public-lane score: Coming soon
- Muse Spark public-lane score: 77.5 (#14/48)

| Benchmark | Claude Sonnet 4.5 Thinking | Muse Spark | Winner |
|-----------|-----------|-----------|--------|
| CharXiv | Coming soon | 86.4% | Coming soon |
| MMMU-Pro | Coming soon | 80.4% | Coming soon |
| ERQA | Coming soon | 64.7% | Coming soon |
| SimpleVQA | Coming soon | 71.3% | Coming soon |
| ScreenSpot Pro | Coming soon | 84.1% | Coming soon |
| ZeroBench | Coming soon | 33.0% | Coming soon |
| MedXpertQA (MM) | Coming soon | 78.4% | Coming soon |

### Reasoning

- Winner: Insufficient shared evidence
- Claude Sonnet 4.5 Thinking public-lane score: Coming soon
- Muse Spark public-lane score: 45.9 (Unranked · 3 rankable rows)

| Benchmark | Claude Sonnet 4.5 Thinking | Muse Spark | Winner |
|-----------|-----------|-----------|--------|
| ARC-AGI-2 | Coming soon | 42.5% | Coming soon |

### Knowledge

- Winner: Insufficient shared evidence
- Claude Sonnet 4.5 Thinking public-lane score: Coming soon
- Muse Spark public-lane score: 65.7 (Supported · #23/181)

| Benchmark | Claude Sonnet 4.5 Thinking | Muse Spark | Winner |
|-----------|-----------|-----------|--------|
| GPQA-D | Coming soon | 89.5% | Coming soon |
| HLE | Coming soon | 50.4% | Coming soon |
| HLE w/o tools | Coming soon | 42.8% | Coming soon |
| HealthBench Hard | Coming soon | 42.8% | Coming soon |
| MedXpertQA (Text) | Coming soon | 52.6% | Coming soon |

### Instruction Following

- Winner: Insufficient shared evidence
- Claude Sonnet 4.5 Thinking public-lane score: Coming soon
- Muse Spark public-lane score: 92.9 (#8/120)

### Mathematics

- Winner: Insufficient shared evidence
- Claude Sonnet 4.5 Thinking public-lane score: Coming soon
- Muse Spark public-lane score: 55.3 (Unranked · 2 rankable rows)

| Benchmark | Claude Sonnet 4.5 Thinking | Muse Spark | Winner |
|-----------|-----------|-----------|--------|
| FrontierMath v2 (Tiers 1-3) | Coming soon | 39.000% | Coming soon |
| FrontierMath v2 (Tier 4) | Coming soon | 14.600% | Coming soon |

## FAQ

### Is there enough evidence to pick between Claude Sonnet 4.5 Thinking and Muse Spark?

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 Sonnet 4.5 Thinking vs Claude Sonnet 4.5](/compare/claude-sonnet-4-5-vs-claude-sonnet-4-5-thinking)
- [Muse Spark vs Claude Sonnet 4.5](/compare/claude-sonnet-4-5-vs-muse-spark)
- [Claude Sonnet 4.5 Thinking vs Muse Spark 1.2](/compare/claude-sonnet-4-5-thinking-vs-muse-spark-1-2)
- [Muse Spark vs Muse Spark 1.2](/compare/muse-spark-vs-muse-spark-1-2)

## Explore More

- [Claude Sonnet 4.5 Thinking profile](/models/claude-sonnet-4-5-thinking)
- [Muse Spark profile](/models/muse-spark)
- [Compare Pricing](/llm-pricing)
- [Alternative Finder](/tools/alternative-finder)
- [LLM Selector](/tools/llm-selector)
- [Overall Rankings](/best/overall)