Model comparison
Gemini 3.6 Flash vs GPT-5.6 Luna
Head-to-head evidence from 17 shared benchmark results across 5 categories. Overall scores shown here use the public BenchAlign v5 ranking lane.
Public leaderboard positions: Gemini 3.6 Flash unranked (Not scored); GPT-5.6 Luna #22 (Estimated). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.
Evidence parity. Gemini 3.6 Flash and GPT-5.6 Luna share 17 comparable benchmark results. 1 of 8 categories are comparable. 2 results are unique to Gemini 3.6 Flash; 24 to GPT-5.6 Luna.
Updated July 21, 2026- Shared results
- 17
- Gemini 3.6 Flash only
- 2
- GPT-5.6 Luna only
- 24
- Comparable categories
- 1 / 8
Treat this as a split decision. Gemini 3.6 Flash makes more sense if its workflow fits your team better; GPT-5.6 Luna is the better fit if agentic is the priority or you want the cheaper token bill.
Confidence note. This is a partial-evidence comparison with 17 shared benchmark results across 5 evidence categories; 1 of 8 categories currently have scoreable aggregates for both models. Treat the verdict as directional until coverage is more balanced.
Why this result
Gemini 3.6 Flash and GPT-5.6 Luna finish on the same BenchAlign overall score, so this is less about a single winner and more about where the edge shows up. The BenchAlign headline says tie; the benchmark table is where the real choice happens.
Gemini 3.6 Flash is also the more expensive model on tokens at $1.50 input / $7.50 output per 1M tokens, versus $1.00 input / $6.00 output per 1M tokens for GPT-5.6 Luna.
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 | Gemini 3.6 Flash | Δ | GPT-5.6 Luna |
|---|---|---|---|
| Agentic | Gemini 3.6 Flash83.0 | Margin→ 1.1 | GPT-5.6 Luna84.1 |
| Coding | Gemini 3.6 FlashNot measured | MarginNo overlap | GPT-5.6 Luna62.7 |
| Knowledge | Gemini 3.6 FlashNot measured | MarginNo overlap | GPT-5.6 Luna92.3 |
| Math | Gemini 3.6 FlashNot measured | MarginNo overlap | GPT-5.6 Luna73.6 |
| Multimodal | Gemini 3.6 FlashNot measured | MarginNo overlap | GPT-5.6 Luna78.4 |
Operational comparison
Runtime and commercial metrics are compared only when both models have a complete sourced value.
| Metric | Gemini 3.6 Flash | GPT-5.6 Luna | Comparison |
|---|---|---|---|
| Input / output priceUSD per 1M tokens | Gemini 3.6 Flash$1.5 input / $7.5 output | GPT-5.6 Luna$1 input / $6 output | GPT-5.6 Luna has the lower combined listed price. |
| Generation speedtokens per second | Gemini 3.6 FlashNot available | GPT-5.6 LunaNot available | A complete speed comparison is not available. |
| First-answer latencyseconds to first token | Gemini 3.6 FlashNot available | GPT-5.6 LunaNot available | A complete latency comparison is not available. |
| Context windowmaximum listed tokens | Gemini 3.6 Flash1M | GPT-5.6 Luna1M | Listed context windows are equal. |
Benchmark Deep Dive
AgenticGPT-5.6 Luna wins17 benchmarks
| Benchmark | Gemini 3.6 Flash | GPT-5.6 Luna | Result |
|---|---|---|---|
| OSWorld-VerifiedSource | 83% | — | Not comparable |
| GDPval-AASource | 1421 | 1584 | GPT-5.6 Luna leads |
| AA Agentic IndexSource | 38.7% | 45.6% | GPT-5.6 Luna leads |
| GDPval-AASource | 46.1% | 54.2% | GPT-5.6 Luna leads |
| AA BriefcaseSource | 961 | — | Not comparable |
| AA Tau3 BankingSource | 24.5% | 27.2% | GPT-5.6 Luna leads |
| aaTerminalBench21Source | 77.5% | 80.9% | GPT-5.6 Luna leads |
| Terminal-Bench 2.0Source | — | 84.7% | Not comparable |
| 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 Harvey LABSource | — | 87.9% | Not comparable |
| AA ITBenchSource | — | 40.3% | Not comparable |
| AA AutomationBenchSource | — | 42.2% | Not comparable |
| APEX-Agents-AASource | — | 35.8% | Not comparable |
Coding7 benchmarks
| Benchmark | Gemini 3.6 Flash | GPT-5.6 Luna | Result |
|---|---|---|---|
| deepSweSource | 49% | 67.2% | GPT-5.6 Luna leads |
| AA Coding IndexSource | 69.2% | 71.5% | GPT-5.6 Luna leads |
| AA-SciCodeSource | 52.7% | 52.5% | Gemini 3.6 Flash leads |
| SWE-bench ProSource | — | 62.7% | Not comparable |
| Terminal-Bench 2.0Source | — | 84.7% | Not comparable |
| FrontierCode 1.1 ExtendedSource | — | 55.1% | Not comparable |
| cursorBench32Source | — | 61.1% | Not comparable |
Reasoning3 benchmarks
Knowledge10 benchmarks
| Benchmark | Gemini 3.6 Flash | GPT-5.6 Luna | Result |
|---|---|---|---|
| Artificial Analysis Intelligence IndexSource | 50.1% | 51.2% | GPT-5.6 Luna leads |
| AA-GPQA DiamondSource | 92.8% | 91.1% | Gemini 3.6 Flash leads |
| AA-HLESource | 38.3% | 37.2% | Gemini 3.6 Flash leads |
| AA-Omniscience IndexSource | 23.5% | -11.2% | Gemini 3.6 Flash leads |
| AA-Omniscience AccuracySource | 50.2% | 41.5% | Gemini 3.6 Flash leads |
| AA-Omniscience Hallucination RateSource | 53.5% | 90.1% | Gemini 3.6 Flash leads |
| GPQASource | — | 92.3% | Not comparable |
| GPQA-DSource | — | 92.3% | Not comparable |
| HealthBench ProfessionalSource | — | 55.7% | Not comparable |
| HealthBench HardSource | — | 32.0% | Not comparable |
Math3 benchmarks
Frequently Asked Questions (2)
Which is better, Gemini 3.6 Flash or GPT-5.6 Luna?
Gemini 3.6 Flash and GPT-5.6 Luna are tied on the BenchAlign overall score, so the right pick depends on which category matters most for your use case.
Which is better for agentic tasks, Gemini 3.6 Flash or GPT-5.6 Luna?
GPT-5.6 Luna has the edge for agentic tasks in this comparison, averaging 84.1 versus 83. Inside this category, GDPval-AA is the benchmark that creates the most daylight between them.
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