# GPT-5.6 Luna vs Muse Spark 1.2 > Side-by-side benchmark comparison for GPT-5.6 Luna and Muse Spark 1.2 across agentic, coding, multimodal, knowledge, reasoning, multilingual, and math tasks. - Canonical page: https://benchlm.ai/compare/gpt-5-6-luna-vs-muse-spark-1-2 - Last updated: September 18, 2026 - Shared sourced benchmarks: 5 - HTML indexing: indexable - Ranking lane: BenchAlign v5 ## Quick Verdict Pick Muse Spark 1.2 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 1.2 leads overall 70.28 to 64.77. - The clearest category separation is in reasoning, where the averages are 51.2 for GPT-5.6 Luna and 75.3 for Muse Spark 1.2. - The biggest single benchmark swing is Terminal-Bench 2.1 (Vals) in Agentic, with scores of 79.0% and 69.7%. - 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 1.2 | |----------|----------|----------| | Creator | OpenAI | Meta | | Type | Proprietary | Proprietary | | Reasoning | Reasoning | Reasoning | | Context | 1.05M | 1M | | Overall Score | 64.77 | 70.28 | | Benchmarks Covered | 30 | 8 | | Pricing (input/output) | $0.20 / $1.20 | $1.25 / $4.25 | ## Category Breakdown ### Agentic - Winner: Muse Spark 1.2 - GPT-5.6 Luna public-lane score: 56.7 (Supported · #34/154) - Muse Spark 1.2 public-lane score: 61 (Supported · #16/154) | Benchmark | GPT-5.6 Luna | Muse Spark 1.2 | Winner | |-----------|-----------|-----------|--------| | Terminal-Bench 3.0 | 14.3% | Coming soon | Coming soon | | Terminal-Bench 2.0 | 84.7% | Coming soon | Coming soon | | BrowseComp | 83.3% | Coming soon | Coming soon | | OSWorld 2.0 | 45.6% | Coming soon | Coming soon | | 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% | 69.7% | GPT-5.6 Luna | | ApprenticeBench | 7% | Coming soon | Coming soon | | Terminal-Bench 2.1 | Coming soon | 82.9% | Coming soon | ### Coding - Winner: GPT-5.6 Luna - GPT-5.6 Luna public-lane score: 66.8 (Supported · #9/154) - Muse Spark 1.2 public-lane score: 60 (Supported · #21/154) | Benchmark | GPT-5.6 Luna | Muse Spark 1.2 | Winner | |-----------|-----------|-----------|--------| | SWE-bench Pro | 62.7% | Coming soon | Coming soon | | Terminal-Bench 2.0 | 84.7% | Coming soon | Coming soon | | DeepSWE | 67.2% | 59.3% | GPT-5.6 Luna | | FrontierCode 1.1 Extended | 55.1% | Coming soon | Coming soon | | cursorBench32 | 61.1% | Coming soon | Coming soon | | VulcanBench v3 | 85.5% | 87.0% | Muse Spark 1.2 | | SWE-bench (Vals) | 93.0% | 86.6% | GPT-5.6 Luna | | cursorBench40 | 35.9% | Coming soon | Coming soon | | Terminal-Bench 2.1 | Coming soon | 82.9% | Coming soon | | FrontierSWE v2 | Coming soon | 12.0% | Coming soon | ### Multimodal & Grounded - Winner: Coming soon - GPT-5.6 Luna public-lane score: 67.1 (#21/48) - Muse Spark 1.2 public-lane score: Coming soon | Benchmark | GPT-5.6 Luna | Muse Spark 1.2 | Winner | |-----------|-----------|-----------|--------| | MMMU-Pro | 78.4% | Coming soon | Coming soon | | MMMU-Pro w/ Python | 79.5% | Coming soon | Coming soon | ### Reasoning - Winner: Coming soon - GPT-5.6 Luna public-lane score: 51.2 (#19/20) - Muse Spark 1.2 public-lane score: 75.3 (Unranked · 2 rankable rows) | Benchmark | GPT-5.6 Luna | Muse Spark 1.2 | Winner | |-----------|-----------|-----------|--------| | ARC-AGI-2 | 59.5% | Coming soon | Coming soon | | ARC-AGI-3 | 0.2% | Coming soon | Coming soon | ### Knowledge - Winner: Coming soon - GPT-5.6 Luna public-lane score: 64.2 (Supported · #27/184) - Muse Spark 1.2 public-lane score: 70.7 (Estimated · #10/184) | Benchmark | GPT-5.6 Luna | Muse Spark 1.2 | 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% | 88.3% | Muse Spark 1.2 | ### Mathematics - Winner: Coming soon - GPT-5.6 Luna public-lane score: 94.2 (Unranked · 3 rankable rows) - Muse Spark 1.2 public-lane score: Coming soon | Benchmark | GPT-5.6 Luna | Muse Spark 1.2 | Winner | |-----------|-----------|-----------|--------| | FrontierMath (legacy) | 78.6% | Coming soon | Coming soon | | FrontierMath v2 (Tiers 1-3) | 78.600% | Coming soon | Coming soon | | FrontierMath v2 (Tier 4) | 58.500% | Coming soon | Coming soon | ## FAQ ### Which is better overall, GPT-5.6 Luna or Muse Spark 1.2? Muse Spark 1.2 is ahead overall on BenchLM right now. ### Where is the biggest gap between GPT-5.6 Luna and Muse Spark 1.2? The widest category gap is in reasoning, where the averages are 51.2 for GPT-5.6 Luna and 75.3 for Muse Spark 1.2. ### How many benchmarks does GPT-5.6 Luna cover on BenchLM? GPT-5.6 Luna currently has 30 sourced benchmark scores on BenchLM. ### How many benchmarks does Muse Spark 1.2 cover on BenchLM? Muse Spark 1.2 currently has 8 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 1.2 vs GPT-5.6 Sol](/compare/gpt-5-6-sol-vs-muse-spark-1-2) - [GPT-5.6 Luna vs GPT-5.6 Terra](/compare/gpt-5-6-luna-vs-gpt-5-6-terra) - [Muse Spark 1.2 vs GPT-5.6 Terra](/compare/gpt-5-6-terra-vs-muse-spark-1-2) ## Explore More - [GPT-5.6 Luna profile](/models/gpt-5-6-luna) - [Muse Spark 1.2 profile](/models/muse-spark-1-2) - [Compare Pricing](/llm-pricing) - [Alternative Finder](/tools/alternative-finder) - [LLM Selector](/tools/llm-selector) - [Overall Rankings](/best/overall)