# Claude Opus 5 vs Gemini 3.5 Flash

> Side-by-side benchmark comparison for Claude Opus 5 and Gemini 3.5 Flash across agentic, coding, multimodal, knowledge, reasoning, multilingual, and math tasks.

- Canonical page: https://benchlm.ai/compare/claude-opus-5-vs-gemini-3-5-flash
- Last updated: September 4, 2026

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

## Quick Verdict

Pick Claude Opus 5 if you want the stronger benchmark profile. Gemini 3.5 Flash only makes more sense when its price, context window, or workload-specific category wins matter more than the overall score.

## Summary

- Claude Opus 5 leads overall 80.66 to 70.
- The clearest category separation is in agentic, where the averages are 77.4 for Claude Opus 5 and 50.6 for Gemini 3.5 Flash.
- The biggest single benchmark swing is HLE in Knowledge, with scores of 64.7% and 40.2%.
- Gemini 3.5 Flash is the cheaper option on output tokens, which matters if you expect large responses or heavy interactive use.
- Gemini 3.5 Flash also has the larger context window at 1M.

## Model Snapshot

| Property | Claude Opus 5 | Gemini 3.5 Flash |
|----------|----------|----------|
| Creator | Anthropic | Google |
| Type | Proprietary | Proprietary |
| Reasoning | Reasoning | Reasoning |
| Context | null | 1M |
| Overall Score | 80.66 | 70 |
| Benchmarks Covered | 73 | 27 |
| Pricing (input/output) | $5.00 / $25.00 | $1.50 / $9.00 |

## Category Breakdown

### Agentic

- Winner: Claude Opus 5
- Claude Opus 5 public-lane score: 77.4 (Supported · #2/151)
- Gemini 3.5 Flash public-lane score: 50.6 (Supported · #61/151)

| Benchmark | Claude Opus 5 | Gemini 3.5 Flash | Winner |
|-----------|-----------|-----------|--------|
| Terminal-Bench 3.0 | 42.7% | Coming soon | Coming soon |
| BrowseComp | 90.8% | Coming soon | Coming soon |
| HLE w/ tools | 64.7% | Coming soon | Coming soon |
| DeepSearchQA | 95.0% | Coming soon | Coming soon |
| DRACO | 88.6% | Coming soon | Coming soon |
| BrowseComp (10-agent, prerelease) | 93.6% | Coming soon | Coming soon |
| OSWorld 2.0 | 70.6% | Coming soon | Coming soon |
| MCP Atlas | 85.8% | 83.6% | Claude Opus 5 |
| MCP-Atlas claim coverage | 89.1% | Coming soon | Coming soon |
| LAB all-pass (Anthropic harness) | 23.58% | Coming soon | Coming soon |
| LAB criterion-pass (Anthropic harness) | 93.74% | Coming soon | Coming soon |
| LAB all-pass (Harvey held-out) | 11.7% | Coming soon | Coming soon |
| LAB criterion-pass (Harvey held-out) | 94.1% | Coming soon | Coming soon |
| Toolathlon-Verified | 80.6% | Coming soon | Coming soon |
| Toolathlon Verified Pass@3 | 87.0% | Coming soon | Coming soon |
| Toolathlon Verified Pass³ | 73.1% | Coming soon | Coming soon |
| Toolathlon Verified avg. turns | 23.5 turns | Coming soon | Coming soon |
| AutomationBench | 26.0% | Coming soon | Coming soon |
| Terminal-Bench 2.1 (Vals) | 84.6% | 74.2% | Claude Opus 5 |
| Terminal-Bench 2.0 | Coming soon | 76.2% | Coming soon |
| Toolathlon | Coming soon | 56.5% | Coming soon |
| OSWorld-Verified | Coming soon | 78.4% | Coming soon |
| Finance Agent v2 | Coming soon | 57.9% | Coming soon |
| Gert Labs | Coming soon | 61.85% | Coming soon |
| ResearchClawBench | Coming soon | 18.0% | Coming soon |

### Coding

- Winner: Claude Opus 5
- Claude Opus 5 public-lane score: 75.6 (Supported · #3/183)
- Gemini 3.5 Flash public-lane score: 57.7 (Supported · #34/183)

| Benchmark | Claude Opus 5 | Gemini 3.5 Flash | Winner |
|-----------|-----------|-----------|--------|
| Bug Hunt Bench | 27 fixes | Coming soon | Coming soon |
| SWE-bench Verified | 96% | Coming soon | Coming soon |
| SWE-bench Pro | 79.2% | 55.1% | Claude Opus 5 |
| SWE Multilingual | 89.5% | Coming soon | Coming soon |
| SWE Multimodal | 59.4% | Coming soon | Coming soon |
| deepSwe | 68.8% | Coming soon | Coming soon |
| FrontierCode 1.1 Main | 53.4% | Coming soon | Coming soon |
| FrontierCode 1.1 Extended | 63.6% | Coming soon | Coming soon |
| FrontierSWE v2 | 52.0% | Coming soon | Coming soon |
| ProgramBench (episode 1) | 83.0% | Coming soon | Coming soon |
| ProgramBench | 93.0% | Coming soon | Coming soon |
| cursorBench32 | 70.0% | 48.8% | Claude Opus 5 |
| VulcanBench v3 | 87.0% | Coming soon | Coming soon |
| VulcanBench CII v1 | 96.4% | Coming soon | Coming soon |
| LiveCodeBench (Vals) | 89.0% | 87.6% | Claude Opus 5 |
| SWE-bench (Vals) | 97.0% | 78.8% | Claude Opus 5 |
| Terminal-Bench 2.0 | Coming soon | 76.2% | Coming soon |
| Vibe Code Bench | Coming soon | 48.68% | Coming soon |
| cursorBench31 | Coming soon | 49.8% | Coming soon |

### Multimodal & Grounded

- Winner: Coming soon
- Claude Opus 5 public-lane score: 88.7 (#2/48)
- Gemini 3.5 Flash public-lane score: 86.9 (#6/48)

| Benchmark | Claude Opus 5 | Gemini 3.5 Flash | Winner |
|-----------|-----------|-----------|--------|
| Chartography (no tools) | 29.6% | Coming soon | Coming soon |
| Chartography (tools) | 83.0% | Coming soon | Coming soon |
| BenchCAD Vision2Code (no tools) | 0.366 | Coming soon | Coming soon |
| BenchCAD Vision2Code (tools) | 0.821 | Coming soon | Coming soon |
| GDP.pdf (no tools) | 83.4% | Coming soon | Coming soon |
| GDP.pdf (tools) | 85.5% | Coming soon | Coming soon |
| OfficeQA | 78.1% | Coming soon | Coming soon |
| OfficeQA Pro | 66.9% | Coming soon | Coming soon |
| CharXiv | Coming soon | 84.2% | Coming soon |
| MMMU-Pro | Coming soon | 83.6% | Coming soon |
| Blueprint-Bench 2 | Coming soon | 33.6% | Coming soon |

### Reasoning

- Winner: Coming soon
- Claude Opus 5 public-lane score: 75.6 (#13/22)
- Gemini 3.5 Flash public-lane score: 60.3 (#17/22)

| Benchmark | Claude Opus 5 | Gemini 3.5 Flash | Winner |
|-----------|-----------|-----------|--------|
| ARC-AGI-1 | 97.50% | Coming soon | Coming soon |
| ARC-AGI-2 | 90.4% | 72.1% | Claude Opus 5 |
| ARC-AGI-3 | 30.2% | Coming soon | Coming soon |
| MRCRv2 | Coming soon | 77.3% | Coming soon |
| MRCR 1M | Coming soon | 26.6% | Coming soon |

### Knowledge

- Winner: Claude Opus 5
- Claude Opus 5 public-lane score: 82.1 (Supported · #3/181)
- Gemini 3.5 Flash public-lane score: 68.5 (Supported · #19/181)

| Benchmark | Claude Opus 5 | Gemini 3.5 Flash | Winner |
|-----------|-----------|-----------|--------|
| HLE | 64.7% | 40.2% | Claude Opus 5 |
| HLE w/o tools | 56.3% | Coming soon | Coming soon |
| HLE-Verified | 54.4% | Coming soon | Coming soon |
| LABBench2 | 84.2% | Coming soon | Coming soon |
| HealthBench (raw) | 67.1% | Coming soon | Coming soon |
| HealthBench (length-adjusted) | 57.8% | Coming soon | Coming soon |
| HealthBench Professional | 59.8% | Coming soon | Coming soon |
| HealthBench Professional (raw) | 73.4% | Coming soon | Coming soon |
| BioMysteryBench (human-solvable) | 90.1% | Coming soon | Coming soon |
| BioMysteryBench (human-difficult) | 49.4% | Coming soon | Coming soon |
| SpatialBench Verified | 72.5% | Coming soon | Coming soon |
| SingleCellBench | 60.6% | Coming soon | Coming soon |
| ProteinGym Hard | 47.7% | Coming soon | Coming soon |
| Protein Design | 42.5% | Coming soon | Coming soon |
| Organic chemistry V2 | 61.6% | Coming soon | Coming soon |
| Protocols (troubleshooting) | 61.1% | Coming soon | Coming soon |
| Protocols (understanding) | 78.4% | Coming soon | Coming soon |
| GPQA Diamond (Vals) | 93.4% | 92.7% | Claude Opus 5 |
| MMLU-Pro (Vals) | 91.6% | 89.5% | Claude Opus 5 |
| GPQA-D | Coming soon | 92.7% | Coming soon |

### Instruction Following

- Winner: Coming soon
- Claude Opus 5 public-lane score: Coming soon
- Gemini 3.5 Flash public-lane score: 86.9 (#34/120)

### Multilingual

- Winner: Coming soon
- Claude Opus 5 public-lane score: Coming soon
- Gemini 3.5 Flash public-lane score: Coming soon

| Benchmark | Claude Opus 5 | Gemini 3.5 Flash | Winner |
|-----------|-----------|-----------|--------|
| GMMLU | 92.5% | Coming soon | Coming soon |
| MILU | 92.1% | Coming soon | Coming soon |
| INCLUDE | 89.8% | Coming soon | Coming soon |

### Mathematics

- Winner: Coming soon
- Claude Opus 5 public-lane score: Coming soon
- Gemini 3.5 Flash public-lane score: 55.2 (Unranked · 2 rankable rows)

| Benchmark | Claude Opus 5 | Gemini 3.5 Flash | Winner |
|-----------|-----------|-----------|--------|
| IMO 2026 | 42/42 | Coming soon | Coming soon |
| RiemannBench (no tools) | 60.0% | Coming soon | Coming soon |
| RiemannBench (tools) | 79.0% | Coming soon | Coming soon |
| ArXivMath Jun. 2026 (no tools) | 90.8% | Coming soon | Coming soon |
| ArXivMath Jun. 2026 (tools) | 91.3% | Coming soon | Coming soon |
| FrontierMath v2 (Tiers 1-3) | Coming soon | 38.966% | Coming soon |
| FrontierMath v2 (Tier 4) | Coming soon | 14.583% | Coming soon |

## FAQ

### Which is better overall, Claude Opus 5 or Gemini 3.5 Flash?

Claude Opus 5 is ahead overall on BenchLM right now.

### Where is the biggest gap between Claude Opus 5 and Gemini 3.5 Flash?

The widest category gap is in agentic, where the averages are 77.4 for Claude Opus 5 and 50.6 for Gemini 3.5 Flash.

### How many benchmarks does Claude Opus 5 cover on BenchLM?

Claude Opus 5 currently has 73 sourced benchmark scores on BenchLM.

### How many benchmarks does Gemini 3.5 Flash cover on BenchLM?

Gemini 3.5 Flash currently has 27 sourced benchmark scores on BenchLM.

## Related Comparisons

- [Claude Opus 5 vs Gemini 3.5 Flash Cyber](/compare/claude-opus-5-vs-gemini-3-5-flash-cyber)
- [Gemini 3.5 Flash vs Gemini 3.5 Flash Cyber](/compare/gemini-3-5-flash-vs-gemini-3-5-flash-cyber)
- [Claude Opus 5 vs Claude Fable 5.1](/compare/claude-fable-5-1-vs-claude-opus-5)
- [Gemini 3.5 Flash vs Claude Fable 5.1](/compare/claude-fable-5-1-vs-gemini-3-5-flash)

## Explore More

- [Claude Opus 5 profile](/models/claude-opus-5)
- [Gemini 3.5 Flash profile](/models/gemini-3-5-flash)
- [Compare Pricing](/llm-pricing)
- [Alternative Finder](/tools/alternative-finder)
- [LLM Selector](/tools/llm-selector)
- [Overall Rankings](/best/overall)