# Composer 2.5 vs Gemini 3.8 Flash

> Side-by-side benchmark comparison for Composer 2.5 and Gemini 3.8 Flash across agentic, coding, multimodal, knowledge, reasoning, multilingual, and math tasks.

- Canonical page: https://benchlm.ai/compare/composer-2-5-vs-gemini-3-8-flash
- Last updated: October 17, 2026

- Shared sourced benchmarks: 4
- HTML indexing: indexable
- Ranking lane: BenchAlign v5.8

## Quick Verdict

Pick Gemini 3.8 Flash if you want the stronger benchmark profile. Composer 2.5 only makes more sense when its price, context window, or workload-specific category wins matter more than the overall score.

## Summary

- Gemini 3.8 Flash leads overall 69.25 to 64.
- The biggest single benchmark swing is Terminal-Bench 2.1 (Vals) in Agentic, with scores of 58.4% and 81.3%.
- Composer 2.5 is the cheaper option on output tokens, which matters if you expect large responses or heavy interactive use.
- Gemini 3.8 Flash also has the larger context window at 1M.

## Model Snapshot

| Property | Composer 2.5 | Gemini 3.8 Flash |
|----------|----------|----------|
| Creator | Cursor | Google |
| Type | Proprietary | Proprietary |
| Reasoning | Reasoning | Reasoning |
| Context | 200K | 1M |
| Overall Score | null | 69.25 |
| Benchmarks Covered | 8 | 31 |
| Pricing (input/output) | $0.50 / $2.50 | $0.75 / $3.75 |

## Category Breakdown

### Agentic

- Winner: Not comparable
- Composer 2.5 public-lane score: Coming soon
- Gemini 3.8 Flash public-lane score: 65.9 (Supported · #16/128)

| Benchmark | Composer 2.5 | Gemini 3.8 Flash | Winner |
|-----------|-----------|-----------|--------|
| Terminal-Bench 2.0 | 69.3% | Coming soon | Coming soon |
| Terminal-Bench 2.1 (Vals) | 58.4% | 81.3% | Gemini 3.8 Flash |
| Finance Agent v2 | Coming soon | 61.4% | Coming soon |
| Terminal-Bench 2.1 | Coming soon | 89.4% | Coming soon |
| Terminal-Bench 4.0 | Coming soon | 19.10% | Coming soon |
| OSWorld 2.0 | Coming soon | 59.0% | Coming soon |
| ApprenticeBench | Coming soon | 24% | Coming soon |
| Hermes Index | Coming soon | 38.1% | Coming soon |
| Hermes Bench | Coming soon | 62.2% | Coming soon |
| MazeBench | Coming soon | 4% | Coming soon |

### Coding

- Winner: Not comparable
- Composer 2.5 public-lane score: Coming soon
- Gemini 3.8 Flash public-lane score: 61 (Supported · #17/150)

| Benchmark | Composer 2.5 | Gemini 3.8 Flash | Winner |
|-----------|-----------|-----------|--------|
| Terminal-Bench 2.0 | 69.3% | Coming soon | Coming soon |
| SWE Multilingual | 79.8% | Coming soon | Coming soon |
| cursorBench31 | 63.2% | Coming soon | Coming soon |
| CursorBench 3.2 | 56.1% | 69.2% | Gemini 3.8 Flash |
| SWE-bench (Vals) | 79.6% | 80.0% | Gemini 3.8 Flash |
| CursorBench 4.0 | 27.7% | 39.6% | Gemini 3.8 Flash |
| DeepSWE | Coming soon | 73.8% | Coming soon |
| Terminal-Bench 2.1 | Coming soon | 89.4% | Coming soon |
| LiveCodeBench (Vals) | Coming soon | 89.5% | Coming soon |
| FrontierSWE v2 | Coming soon | 19.6% | Coming soon |
| Bug Hunt Bench | Coming soon | 18.0 fixes | Coming soon |

### Reasoning

- Winner: Not comparable
- Composer 2.5 public-lane score: Coming soon
- Gemini 3.8 Flash public-lane score: 74.3 (#17/28)

| Benchmark | Composer 2.5 | Gemini 3.8 Flash | Winner |
|-----------|-----------|-----------|--------|
| ARC-AGI-1 | Coming soon | 98.50% | Coming soon |
| ARC-AGI-2 | Coming soon | 89.2% | Coming soon |
| ARC-AGI-3 | Coming soon | 10.4% | Coming soon |

### Multimodal & Grounded

- Winner: Not comparable
- Composer 2.5 public-lane score: Coming soon
- Gemini 3.8 Flash public-lane score: 87.3 (#9/54)

| Benchmark | Composer 2.5 | Gemini 3.8 Flash | Winner |
|-----------|-----------|-----------|--------|
| CharXiv w/o tools | Coming soon | 86.2% | Coming soon |
| LVBench | Coming soon | 87.1% | Coming soon |

### Knowledge

- Winner: Not comparable
- Composer 2.5 public-lane score: Coming soon
- Gemini 3.8 Flash public-lane score: 73.5 (Supported · #13/184)

| Benchmark | Composer 2.5 | Gemini 3.8 Flash | Winner |
|-----------|-----------|-----------|--------|
| HLE-Verified | Coming soon | 54.9% | Coming soon |
| LABBench2 | Coming soon | 86.2% | Coming soon |
| BioMysteryBench (human-solvable) | Coming soon | 88.8% | Coming soon |
| BioMysteryBench (human-difficult) | Coming soon | 56.5% | Coming soon |
| GPQA Diamond (Vals) | Coming soon | 94.4% | Coming soon |
| MMLU-Pro (Vals) | Coming soon | 90.2% | Coming soon |

### Instruction Following

- Winner: Not comparable
- Composer 2.5 public-lane score: Coming soon
- Gemini 3.8 Flash public-lane score: Coming soon

| Benchmark | Composer 2.5 | Gemini 3.8 Flash | Winner |
|-----------|-----------|-----------|--------|
| Gray Swan IPI (15 attempts) | Coming soon | 5.5% | Coming soon |

### Mathematics

- Winner: Not comparable
- Composer 2.5 public-lane score: Coming soon
- Gemini 3.8 Flash public-lane score: 69.7 (Unranked · 2 rankable rows)

| Benchmark | Composer 2.5 | Gemini 3.8 Flash | Winner |
|-----------|-----------|-----------|--------|
| FrontierMath v2 (Tiers 1-3) | Coming soon | 68.421% | Coming soon |
| FrontierMath v2 (Tier 4) | Coming soon | 21.951% | Coming soon |

## FAQ

### Which is better overall, Composer 2.5 or Gemini 3.8 Flash?

Gemini 3.8 Flash is ahead overall on BenchLM right now.

### How many benchmarks does Composer 2.5 cover on BenchLM?

Composer 2.5 currently has 8 sourced benchmark scores on BenchLM.

### How many benchmarks does Gemini 3.8 Flash cover on BenchLM?

Gemini 3.8 Flash currently has 31 sourced benchmark scores on BenchLM.

## Related Comparisons

- [Composer 2.5 vs Composer 2](/compare/composer-2-vs-composer-2-5)
- [Gemini 3.8 Flash vs Composer 2](/compare/composer-2-vs-gemini-3-8-flash)
- [Composer 2.5 vs Composer 2 Fast](/compare/composer-2-5-vs-composer-2-fast)
- [Gemini 3.8 Flash vs Composer 2 Fast](/compare/composer-2-fast-vs-gemini-3-8-flash)

## Explore More

- [Composer 2.5 profile](/models/composer-2-5)
- [Gemini 3.8 Flash profile](/models/gemini-3-8-flash)
- [Compare Pricing](/llm-pricing)
- [Alternative Finder](/tools/alternative-finder)
- [LLM Selector](/tools/llm-selector)
- [Overall Rankings](/best/overall)