# Gemini 3.5 Flash vs GPT-6 Luna

> Side-by-side benchmark comparison for Gemini 3.5 Flash and GPT-6 Luna across agentic, coding, multimodal, knowledge, reasoning, multilingual, and math tasks.

- Canonical page: https://benchlm.ai/compare/gemini-3-5-flash-vs-gpt-6-luna
- Last updated: September 22, 2026

- Shared sourced benchmarks: 0
- HTML indexing: indexable
- Ranking lane: BenchAlign v5

## Quick Verdict

No benchmark verdict yet: there is no shared sourced benchmark row for Gemini 3.5 Flash and GPT-6 Luna.

## Summary

- Gemini 3.5 Flash and GPT-6 Luna do not currently share a sourced benchmark row. The mirror therefore compares metadata, pricing, context windows, and each model's separately reported coverage without naming a benchmark winner.

## Model Snapshot

| Property | Gemini 3.5 Flash | GPT-6 Luna |
|----------|----------|----------|
| Creator | Google | OpenAI |
| Type | Proprietary | Proprietary |
| Reasoning | Reasoning | Reasoning |
| Context | 1M | 1.05M |
| Independent public score (not head-to-head) | 68.02 | 62.33 |
| Benchmarks Covered | 27 | 7 |
| Pricing (input/output) | $1.50 / $9.00 | $0.10 / $0.50 |

## Category Breakdown

### Agentic

- Winner: Insufficient shared evidence
- Gemini 3.5 Flash public-lane score: 52.8 (Supported · #45/157)
- GPT-6 Luna public-lane score: 56.7 (Estimated · #35/157)

| Benchmark | Gemini 3.5 Flash | GPT-6 Luna | Winner |
|-----------|-----------|-----------|--------|
| Terminal-Bench 2.0 | 76.2% | Coming soon | Coming soon |
| MCP Atlas | 83.6% | Coming soon | Coming soon |
| Toolathlon | 56.5% | Coming soon | Coming soon |
| OSWorld-Verified | 78.4% | Coming soon | Coming soon |
| Finance Agent v2 | 57.9% | Coming soon | Coming soon |
| Gert Labs | 61.85% | Coming soon | Coming soon |
| ResearchClawBench | 18.0% | Coming soon | Coming soon |
| Terminal-Bench 2.1 (Vals) | 74.2% | Coming soon | Coming soon |
| ExploitGym | Coming soon | 11.6% | Coming soon |

### Coding

- Winner: Insufficient shared evidence
- Gemini 3.5 Flash public-lane score: 57.2 (Supported · #34/159)
- GPT-6 Luna public-lane score: 66.6 (Estimated · #11/159)

| Benchmark | Gemini 3.5 Flash | GPT-6 Luna | Winner |
|-----------|-----------|-----------|--------|
| Terminal-Bench 2.0 | 76.2% | Coming soon | Coming soon |
| SWE-bench Pro | 55.1% | Coming soon | Coming soon |
| Vibe Code Bench | 48.68% | Coming soon | Coming soon |
| cursorBench31 | 49.8% | Coming soon | Coming soon |
| cursorBench32 | 48.8% | Coming soon | Coming soon |
| LiveCodeBench (Vals) | 87.6% | Coming soon | Coming soon |
| SWE-bench (Vals) | 78.8% | Coming soon | Coming soon |
| DeepSWE | Coming soon | 66.6% | Coming soon |

### Reasoning

- Winner: Insufficient shared evidence
- Gemini 3.5 Flash public-lane score: 59.4 (#13/17)
- GPT-6 Luna public-lane score: 78.3 (Unranked · 2 rankable rows)

| Benchmark | Gemini 3.5 Flash | GPT-6 Luna | Winner |
|-----------|-----------|-----------|--------|
| MRCRv2 | 77.3% | Coming soon | Coming soon |
| MRCR 1M | 26.6% | Coming soon | Coming soon |
| ARC-AGI-2 | 72.1% | Coming soon | Coming soon |

### Multimodal & Grounded

- Winner: Insufficient shared evidence
- Gemini 3.5 Flash public-lane score: 86.8 (#7/50)
- GPT-6 Luna public-lane score: 71.3 (Unranked · 1 rankable row)

| Benchmark | Gemini 3.5 Flash | GPT-6 Luna | Winner |
|-----------|-----------|-----------|--------|
| CharXiv | 84.2% | Coming soon | Coming soon |
| MMMU-Pro | 83.6% | Coming soon | Coming soon |
| Blueprint-Bench 2 | 33.6% | Coming soon | Coming soon |

### Knowledge

- Winner: Insufficient shared evidence
- Gemini 3.5 Flash public-lane score: 67.5 (Supported · #21/189)
- GPT-6 Luna public-lane score: 63.6 (Estimated · #29/189)

| Benchmark | Gemini 3.5 Flash | GPT-6 Luna | Winner |
|-----------|-----------|-----------|--------|
| GPQA-D | 92.7% | Coming soon | Coming soon |
| HLE | 40.2% | Coming soon | Coming soon |
| GPQA Diamond (Vals) | 92.7% | Coming soon | Coming soon |
| MMLU-Pro (Vals) | 89.5% | Coming soon | Coming soon |
| HealthBench (raw) | Coming soon | 50.0% | Coming soon |
| HealthBench (length-adjusted) | Coming soon | 54.5% | Coming soon |
| HealthBench Professional | Coming soon | 60.8% | Coming soon |
| HealthBench Professional (raw) | Coming soon | 61.2% | Coming soon |
| HealthBench Hard | Coming soon | 31.4% | Coming soon |

### Instruction Following

- Winner: Insufficient shared evidence
- Gemini 3.5 Flash public-lane score: 84.1 (#43/124)
- GPT-6 Luna public-lane score: Coming soon

### Mathematics

- Winner: Insufficient shared evidence
- Gemini 3.5 Flash public-lane score: 55.1 (Unranked · 2 rankable rows)
- GPT-6 Luna public-lane score: Coming soon

| Benchmark | Gemini 3.5 Flash | GPT-6 Luna | Winner |
|-----------|-----------|-----------|--------|
| FrontierMath v2 (Tiers 1-3) | 38.966% | Coming soon | Coming soon |
| FrontierMath v2 (Tier 4) | 14.583% | Coming soon | Coming soon |

## FAQ

### Can I compare Gemini 3.5 Flash and GPT-6 Luna on BenchLM yet?

Not fully yet. BenchLM is tracking both models, but sourced benchmark coverage is still incomplete for a fair score-level comparison.

### Why does this page show "coming soon" values?

BenchLM only calls winners when public benchmark coverage is available on both sides of the comparison.

## Related Comparisons

- [Gemini 3.5 Flash vs Gemini 3.5 Flash Cyber](/compare/gemini-3-5-flash-vs-gemini-3-5-flash-cyber)
- [GPT-6 Luna vs Gemini 3.5 Flash Cyber](/compare/gemini-3-5-flash-cyber-vs-gpt-6-luna)
- [Gemini 3.5 Flash vs GPT-6 Astra](/compare/gemini-3-5-flash-vs-gpt-6-astra)
- [GPT-6 Luna vs GPT-6 Astra](/compare/gpt-6-astra-vs-gpt-6-luna)

## Explore More

- [Gemini 3.5 Flash profile](/models/gemini-3-5-flash)
- [GPT-6 Luna profile](/models/gpt-6-luna)
- [Compare Pricing](/llm-pricing)
- [Alternative Finder](/tools/alternative-finder)
- [LLM Selector](/tools/llm-selector)
- [Overall Rankings](/best/overall)