# GPT-5.6 Luna vs Muse Spark 1.3

> Side-by-side benchmark comparison for GPT-5.6 Luna and Muse Spark 1.3 across agentic, coding, multimodal, knowledge, reasoning, multilingual, and math tasks.

- Canonical page: https://benchlm.ai/compare/gpt-5-6-luna-vs-muse-spark-1-3
- Last updated: October 17, 2026

- Shared sourced benchmarks: 10
- HTML indexing: indexable
- Ranking lane: BenchAlign v5.8

## Quick Verdict

Pick Muse Spark 1.3 if you want the stronger benchmark profile. GPT-5.6 Luna only makes more sense when its price, context window, or workload-specific category wins matter more than the overall score.

## Summary

- Muse Spark 1.3 leads overall 73 to 64.35.
- The clearest category separation is in reasoning, where the averages are 58.2 for GPT-5.6 Luna and 82.9 for Muse Spark 1.3.
- The biggest single benchmark swing is OSWorld 2.0 in Agentic, with scores of 45.6% and 66.9%.
- GPT-5.6 Luna is the cheaper option on output tokens, which matters if you expect large responses or heavy interactive use.
- GPT-5.6 Luna also has the larger context window at 1.05M.

## Model Snapshot

| Property | GPT-5.6 Luna | Muse Spark 1.3 |
|----------|----------|----------|
| Creator | OpenAI | Meta |
| Type | Proprietary | Proprietary |
| Reasoning | Reasoning | Reasoning |
| Context | 1.05M | 1M |
| Overall Score | 64.35 | null |
| Benchmarks Covered | 32 | 20 |
| Pricing (input/output) | $0.20 / $1.20 | $1.25 / $4.25 |

## Category Breakdown

### Agentic

- Winner: Not comparable
- GPT-5.6 Luna public-lane score: 56 (Supported · #39/128)
- Muse Spark 1.3 public-lane score: Coming soon

| Benchmark | GPT-5.6 Luna | Muse Spark 1.3 | Winner |
|-----------|-----------|-----------|--------|
| Terminal-Bench 3.0 | 14.3% | Coming soon | Coming soon |
| Terminal-Bench 2.1 | 84.7% | 88.8% | Muse Spark 1.3 |
| BrowseComp | 83.3% | Coming soon | Coming soon |
| OSWorld 2.0 | 45.6% | 66.9% | Muse Spark 1.3 |
| CyberGym | 77.9% | Coming soon | Coming soon |
| ExploitGym | 12.4% | Coming soon | Coming soon |
| Toolathlon | 53.4% | Coming soon | Coming soon |
| Terminal-Bench 2.1 (Vals) | 79.0% | 72.3% | GPT-5.6 Luna |
| ApprenticeBench | 7% | 19% | Muse Spark 1.3 |
| MazeBench | 0% | 0% | Tie |
| JobBench | Coming soon | 64.9% | Coming soon |
| DeepSearchQA | Coming soon | 89.4% | Coming soon |
| AutomationBench | Coming soon | 49.4% | Coming soon |
| CWE-bench v1 | Coming soon | 55.0% | Coming soon |

### Coding

- Winner: Not comparable
- GPT-5.6 Luna public-lane score: 61.6 (Supported · #16/150)
- Muse Spark 1.3 public-lane score: Coming soon

| Benchmark | GPT-5.6 Luna | Muse Spark 1.3 | Winner |
|-----------|-----------|-----------|--------|
| SWE-bench Pro | 62.7% | Coming soon | Coming soon |
| Terminal-Bench 2.1 | 84.7% | 88.8% | Muse Spark 1.3 |
| DeepSWE | 67.2% | 75.4% | Muse Spark 1.3 |
| FrontierCode 1.1 Extended | 55.1% | Coming soon | Coming soon |
| CursorBench 3.2 | 61.1% | Coming soon | Coming soon |
| VulcanBench v3 | 85.5% | Coming soon | Coming soon |
| SWE-bench (Vals) | 93.0% | Coming soon | Coming soon |
| CursorBench 4.0 | 35.9% | 41.6% | Muse Spark 1.3 |
| SWE-Atlas Codebase QnA | Coming soon | 59.4% | Coming soon |
| Bug Hunt Bench | Coming soon | 32.2 fixes | Coming soon |
| FrontierSWE v2 | Coming soon | 25.8% | Coming soon |

### Reasoning

- Winner: Directional only
- GPT-5.6 Luna public-lane score: 58.2 (#27/28)
- Muse Spark 1.3 public-lane score: 82.9 (#6/28)

| Benchmark | GPT-5.6 Luna | Muse Spark 1.3 | Winner |
|-----------|-----------|-----------|--------|
| ARC-AGI-2 | 59.5% | Coming soon | Coming soon |
| ARC-AGI-3 | 0.2% | Coming soon | Coming soon |
| ARC-AGI-1 | 88.00% | Coming soon | Coming soon |
| MRCR v2 256K-512K | Coming soon | 98.5% | Coming soon |
| MRCR v2 512K-1M | Coming soon | 98.1% | Coming soon |

### Multimodal & Grounded

- Winner: Not comparable
- GPT-5.6 Luna public-lane score: 79.6 (#19/54)
- Muse Spark 1.3 public-lane score: Coming soon

| Benchmark | GPT-5.6 Luna | Muse Spark 1.3 | Winner |
|-----------|-----------|-----------|--------|
| MMMU-Pro | 78.4% | Coming soon | Coming soon |
| MMMU-Pro w/ Python | 79.5% | Coming soon | Coming soon |

### Knowledge

- Winner: Not comparable
- GPT-5.6 Luna public-lane score: 64.8 (Supported · #37/184)
- Muse Spark 1.3 public-lane score: Coming soon

| Benchmark | GPT-5.6 Luna | Muse Spark 1.3 | Winner |
|-----------|-----------|-----------|--------|
| GPQA | 92.3% | Coming soon | Coming soon |
| GPQA-D | 92.3% | Coming soon | Coming soon |
| HealthBench Professional | 55.7% | Coming soon | Coming soon |
| HealthBench Hard | 32.0% | Coming soon | Coming soon |
| GPQA Diamond (Vals) | 91.7% | Coming soon | Coming soon |
| MMLU-Pro (Vals) | 86.0% | Coming soon | Coming soon |

### Instruction Following

- Winner: Not comparable
- GPT-5.6 Luna public-lane score: Coming soon
- Muse Spark 1.3 public-lane score: Coming soon

| Benchmark | GPT-5.6 Luna | Muse Spark 1.3 | Winner |
|-----------|-----------|-----------|--------|
| Gray Swan IPI (15 attempts) | Coming soon | 15.9% | Coming soon |

### Mathematics

- Winner: Not comparable
- GPT-5.6 Luna public-lane score: 84 (Unranked · 3 rankable rows)
- Muse Spark 1.3 public-lane score: 78.5 (Unranked · 2 rankable rows)

| Benchmark | GPT-5.6 Luna | Muse Spark 1.3 | Winner |
|-----------|-----------|-----------|--------|
| FrontierMath (legacy) | 78.6% | Coming soon | Coming soon |
| FrontierMath v2 (Tiers 1-3) | 78.600% | 74.035% | GPT-5.6 Luna |
| FrontierMath v2 (Tier 4) | 58.500% | 46.341% | GPT-5.6 Luna |

## FAQ

### Which is better overall, GPT-5.6 Luna or Muse Spark 1.3?

Muse Spark 1.3 is ahead overall on BenchLM right now.

### Where is the biggest gap between GPT-5.6 Luna and Muse Spark 1.3?

The widest category gap is in reasoning, where the averages are 58.2 for GPT-5.6 Luna and 82.9 for Muse Spark 1.3.

### How many benchmarks does GPT-5.6 Luna cover on BenchLM?

GPT-5.6 Luna currently has 32 sourced benchmark scores on BenchLM.

### How many benchmarks does Muse Spark 1.3 cover on BenchLM?

Muse Spark 1.3 currently has 20 sourced benchmark scores on BenchLM.

## Related Comparisons

- [GPT-5.6 Luna vs GPT-5.6 Sol](/compare/gpt-5-6-luna-vs-gpt-5-6-sol)
- [Muse Spark 1.3 vs GPT-5.6 Sol](/compare/gpt-5-6-sol-vs-muse-spark-1-3)
- [GPT-5.6 Luna vs GPT-5.6 Terra](/compare/gpt-5-6-luna-vs-gpt-5-6-terra)
- [Muse Spark 1.3 vs GPT-5.6 Terra](/compare/gpt-5-6-terra-vs-muse-spark-1-3)

## Explore More

- [GPT-5.6 Luna profile](/models/gpt-5-6-luna)
- [Muse Spark 1.3 profile](/models/muse-spark-1-3)
- [Compare Pricing](/llm-pricing)
- [Alternative Finder](/tools/alternative-finder)
- [LLM Selector](/tools/llm-selector)
- [Overall Rankings](/best/overall)