Model comparison
GPT-5.6 Luna vs Hy3 Preview
Head-to-head evidence from 17 shared benchmark results across 4 categories. Overall scores shown here use BenchLM's provisional ranking lane.
Evidence parity. GPT-5.6 Luna and Hy3 Preview share 17 comparable benchmark results. 3 of 8 categories are comparable. 23 results are unique to GPT-5.6 Luna; 5 to Hy3 Preview.
Updated July 14, 2026- Shared results
- 17
- GPT-5.6 Luna only
- 23
- Hy3 Preview only
- 5
- Comparable categories
- 3 / 8
Pick GPT-5.6 Luna if you want the stronger benchmark profile. Hy3 Preview only becomes the better choice if you want the cheaper token bill.
Confidence note. This is a partial-evidence comparison with 17 shared benchmark results across 4 evidence categories; 3 of 8 categories currently have scoreable aggregates for both models. Treat the verdict as directional until coverage is more balanced.
Why this result
GPT-5.6 Luna is clearly ahead on the provisional aggregate, 82 to 54. The gap is large enough that you do not need to squint at the spreadsheet to see the difference.
GPT-5.6 Luna's sharpest advantage is in knowledge, where it averages 92.3 against 33.8. The single biggest benchmark swing on the page is Terminal-Bench 2.0, 84.7% to 54.4%.
GPT-5.6 Luna is also the more expensive model on tokens at $1.00 input / $6.00 output per 1M tokens, versus $0.00 input / $0.00 output per 1M tokens for Hy3 Preview. That is roughly Infinityx on output cost alone. GPT-5.6 Luna gives you the larger context window at 1M, compared with 256K for Hy3 Preview.
Category breakdown
Exact category averages are shown below. Not measured means BenchLM does not have enough sourced public coverage for that model and category.
| Category | GPT-5.6 Luna | Δ | Hy3 Preview |
|---|---|---|---|
| Knowledge | GPT-5.6 Luna92.3 | Margin← 58.5 | Hy3 Preview33.8 |
| Agentic | GPT-5.6 Luna84.1 | Margin← 29.7 | Hy3 Preview54.4 |
| Coding | GPT-5.6 Luna62.7 | Margin← 1.1 | Hy3 Preview61.6 |
| Math | GPT-5.6 Luna73.6 | MarginNo overlap | Hy3 PreviewNot measured |
| Multimodal | GPT-5.6 Luna78.4 | MarginNo overlap | Hy3 PreviewNot measured |
| Inst. Following | GPT-5.6 LunaNot measured | MarginNo overlap | Hy3 Preview63.1 |
Decisive benchmark drivers
The largest measured benchmark gaps in this matchup, with exact reported values.
More
- Source ↗
Terminal-Bench 2.0
AgenticA 84.7%B 54.4%Winner: GPT-5.6 LunaΔ 30.3Terminal-Bench 2.0: GPT-5.6 Luna scored 84.7%; Hy3 Preview scored 54.4%. GPT-5.6 Luna wins this benchmark. - Source ↗
GPQA
KnowledgeA 92.3%B 87.2%Winner: GPT-5.6 LunaΔ 5.1GPQA: GPT-5.6 Luna scored 92.3%; Hy3 Preview scored 87.2%. GPT-5.6 Luna wins this benchmark.
Operational comparison
Runtime and commercial metrics are compared only when both models have a complete sourced value.
| Metric | GPT-5.6 Luna | Hy3 Preview | Comparison |
|---|---|---|---|
| Input / output priceUSD per 1M tokens | GPT-5.6 Luna$1 input / $6 output | Hy3 Preview$0 input / $0 output | Hy3 Preview has the lower combined listed price. |
| Generation speedtokens per second | GPT-5.6 LunaNot available | Hy3 PreviewNot available | A complete speed comparison is not available. |
| First-answer latencyseconds to first token | GPT-5.6 LunaNot available | Hy3 PreviewNot available | A complete latency comparison is not available. |
| Context windowmaximum listed tokens | GPT-5.6 Luna1M | Hy3 Preview256K | GPT-5.6 Luna lists the larger context window. |
Benchmark Deep Dive
AgenticGPT-5.6 Luna wins14 benchmarks
| Benchmark | GPT-5.6 Luna | Hy3 Preview | Result |
|---|---|---|---|
| Terminal-Bench 2.0Source | 84.7% | 54.4% | GPT-5.6 Luna leads |
| BrowseCompSource | 83.3% | — | Not comparable |
| OSWorld 2.0Source | 45.6% | — | Not comparable |
| CyberGymSource | 77.9% | — | Not comparable |
| ExploitGymSource | 12.4% | — | Not comparable |
| ToolathlonSource | 53.4% | — | Not comparable |
| AA Agentic IndexSource | 45.6% | 30.7% | GPT-5.6 Luna leads |
| GDPval-AASource | 54.6% | 35.7% | GPT-5.6 Luna leads |
| GDPval-AASource | 1592 | 1214 | GPT-5.6 Luna leads |
| AA Harvey LABSource | 5.0% | — | Not comparable |
| AA ITBenchSource | 40.3% | — | Not comparable |
| AA Tau3 BankingSource | 27.2% | — | Not comparable |
| AA AutomationBenchSource | 42.2% | — | Not comparable |
| Gert LabsSource | — | 36.91% | Not comparable |
CodingGPT-5.6 Luna wins10 benchmarks
| Benchmark | GPT-5.6 Luna | Hy3 Preview | Result |
|---|---|---|---|
| SWE-bench ProSource | 62.7% | — | Not comparable |
| Terminal-Bench 2.0Source | 84.7% | 54.4% | GPT-5.6 Luna leads |
| deepSweSource | 67.2% | — | Not comparable |
| FrontierCode 1.1 ExtendedSource | 55.1% | — | Not comparable |
| cursorBench32Source | 61.1% | — | Not comparable |
| AA Coding IndexSource | 71.5% | 58.8% | GPT-5.6 Luna leads |
| AA-SciCodeSource | 52.5% | 47.6% | GPT-5.6 Luna leads |
| AA Terminal-Bench 2.1Source | 80.9% | — | Not comparable |
| SWE-bench VerifiedSource | — | 74.4% | Not comparable |
| SciCodeSource | — | 41.2% | Not comparable |
Reasoning3 benchmarks
KnowledgeGPT-5.6 Luna wins11 benchmarks
| Benchmark | GPT-5.6 Luna | Hy3 Preview | Result |
|---|---|---|---|
| GPQASource | 92.3% | 87.2% | GPT-5.6 Luna leads |
| GPQA-DSource | 92.3% | 87.2% | GPT-5.6 Luna leads |
| HealthBench ProfessionalSource | 55.7% | — | Not comparable |
| HealthBench HardSource | 32.0% | — | Not comparable |
| Artificial Analysis Intelligence IndexSource | 51.2% | 41.2% | GPT-5.6 Luna leads |
| AA-GPQA DiamondSource | 91.1% | 89.7% | GPT-5.6 Luna leads |
| AA-HLESource | 37.2% | 31.6% | GPT-5.6 Luna leads |
| AA-Omniscience IndexSource | -11.2% | -18.5% | GPT-5.6 Luna leads |
| AA-Omniscience AccuracySource | 41.5% | 31.5% | GPT-5.6 Luna leads |
| AA-Omniscience Hallucination RateSource | 90.1% | 73.0% | Hy3 Preview leads |
| HLESource | — | 25.5% | Not comparable |
Math3 benchmarks
Multimodal3 benchmarks
Inst. Following1 benchmarks
| Benchmark | GPT-5.6 Luna | Hy3 Preview | Result |
|---|---|---|---|
| IFBenchSource | — | 63.1% | Not comparable |
Frequently Asked Questions (4)
Which is better, GPT-5.6 Luna or Hy3 Preview?
GPT-5.6 Luna is ahead on BenchLM's provisional leaderboard, 82 to 54. The biggest single separator in this matchup is Terminal-Bench 2.0, where the scores are 84.7% and 54.4%.
Which is better for knowledge tasks, GPT-5.6 Luna or Hy3 Preview?
GPT-5.6 Luna has the edge for knowledge tasks in this comparison, averaging 92.3 versus 33.8. Inside this category, AA-Omniscience Hallucination Rate is the benchmark that creates the most daylight between them.
Which is better for coding, GPT-5.6 Luna or Hy3 Preview?
GPT-5.6 Luna has the edge for coding in this comparison, averaging 62.7 versus 61.6. Inside this category, Terminal-Bench 2.0 is the benchmark that creates the most daylight between them.
Which is better for agentic tasks, GPT-5.6 Luna or Hy3 Preview?
GPT-5.6 Luna has the edge for agentic tasks in this comparison, averaging 84.1 versus 54.4. Inside this category, GDPval-AA is the benchmark that creates the most daylight between them.
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