# Claude Opus 5 vs Qwen3.5-Flash

> Claude Opus 5 is the stronger model overall, scoring 67.7 to 42.3 on the Noometry Index. Qwen3.5-Flash costs 57× less per token, which makes it the better buy when Claude Opus 5's lead doesn't matter for your workload.

- Canonical page: https://noometry.com/compare/claude-opus-5-vs-qwen3-5-flash
- Last updated: 2026-10-10
- Shared benchmarks: 29

## Summary

- They share 29 benchmarks with published results for both. Claude Opus 5 scores higher in 8 categories and Qwen3.5-Flash in 0 categories; 8 gaps are clear of the uncertainty.
- The widest gap is in math, where Claude Opus 5 leads 86.1 to 36.3.
- The biggest single-benchmark swing is FrontierMath (Tiers 1-3): 85.6% for Claude Opus 5 and 18.2% for Qwen3.5-Flash.
- Qwen3.5-Flash is cheaper at $0.10 / $0.40 per million input/output tokens, against $5 / $25 for Claude Opus 5.

## Snapshot

| | Claude Opus 5 | Qwen3.5-Flash |
|---|---|---|
| Provider | Anthropic | Alibaba (Qwen) |
| Noometry Index | 67.7 | 42.3 |
| Rank | 4 | 105 |
| Context | 1M | 1M |
| Input $/M | $5 | $0.10 |
| Output $/M | $25 | $0.40 |
| Weights | Proprietary | Proprietary |

## Coding

- Claude Opus 5: 67.0 (#5)
- Qwen3.5-Flash: 33.9 (#234)

| Benchmark | Claude Opus 5 | Qwen3.5-Flash |
|---|---|---|
| LMArena WebDev | 1694 | 1243 |
| LMArena Coding | 1533 | 1412 |
| ALE-Bench | 2,165 | 221.8 |
| DeepSWE | 73.6% | — |
| FrontierCode | 53.4% | — |
| CursorBench | 46.6% | — |
| FrontierSWE | 52% | — |
| SciCode | 56.4% | — |
| WeirdML | 91.8% | — |

## Agentic & Tool Use

- Claude Opus 5: 55.5 (#1)
- Qwen3.5-Flash: —

| Benchmark | Claude Opus 5 | Qwen3.5-Flash |
|---|---|---|
| Vending-Bench 2 | 11,182 | 462.69 |
| APEX-Agents | 65.8% | — |
| OSWorld 2.0 | 31.4% | — |
| τ²-bench Banking | 48.7% | — |
| PostTrainBench | 35% | — |
| BALROG | 63.4% | — |
| GBAEval | 79.6% | — |
| GDP.pdf | 24% | — |

## Reasoning

- Claude Opus 5: 77.1 (#3)
- Qwen3.5-Flash: 32.9 (#63)

| Benchmark | Claude Opus 5 | Qwen3.5-Flash |
|---|---|---|
| Chess Puzzles | 42% | 21% |
| LMArena Hard Prompts | 1525 | 1404 |
| Mystery Game Puzzles | 59% | 20% |
| DTBench | 97.9% | 82.9% |
| LMCA | 64.5% | 29.1% |
| Epoch Capabilities Index | 162.67 | 143.98 |
| ARC-AGI-2 | 90.4% | — |
| SimpleBench | 80.6% | — |
| NYT Connections (extended) | 94.3% | — |
| ARC-AGI-1 | 97.5% | — |
| CritPt | 29.1% | — |
| EBR-Bench | 45.7% | — |
| Bench to the Future 3 | 0.12 | — |

## Math

- Claude Opus 5: 86.1 (#6)
- Qwen3.5-Flash: 36.3 (#117)

| Benchmark | Claude Opus 5 | Qwen3.5-Flash |
|---|---|---|
| FrontierMath (Tiers 1-3) | 85.6% | 18.2% |
| OTIS Mock AIME 2024-2025 | 98.9% | 84.4% |
| LMArena Math | 1533 | 1407 |
| FrontierMath Tier 4 | 73.2% | — |
| ProofBench | 99% | — |
| FrontierMath (Feb 2025 set) | — | 6.2% |
| FrontierMath Tier 4 (v1) | — | 0% |

## Knowledge

- Claude Opus 5: 66.8 (#8)
- Qwen3.5-Flash: 43.2 (#84)

| Benchmark | Claude Opus 5 | Qwen3.5-Flash |
|---|---|---|
| GPQA Diamond | 93.9% | 82.3% |
| SimpleQA Verified | 59.9% | 20.3% |
| LMArena Expert | 1558 | 1408 |
| Vectara Hallucination Rate | — | 10.5% |

## Multimodal

- Claude Opus 5: 51.1 (#6)
- Qwen3.5-Flash: —

| Benchmark | Claude Opus 5 | Qwen3.5-Flash |
|---|---|---|
| LMArena Vision | 1321 | — |
| Blueprint-Bench 2 | 30.4% | — |
| Furniture Assembly | 60.8% | — |
| LMArena Document | 1516 | — |

## Multilingual

- Claude Opus 5: 58.8 (#3)
- Qwen3.5-Flash: 50.7 (#116)

| Benchmark | Claude Opus 5 | Qwen3.5-Flash |
|---|---|---|
| LMArena Non-English | 1500 | 1385 |
| LMArena Chinese | 1575 | 1446 |
| LMArena French | 1522 | 1412 |
| LMArena German | 1522 | 1389 |
| LMArena Japanese | 1510 | 1369 |
| LMArena Korean | 1526 | 1344 |
| LMArena Russian | 1507 | 1379 |
| LMArena Spanish | 1519 | 1399 |

## Instruction Following

- Claude Opus 5: 79.3 (#5)
- Qwen3.5-Flash: 72.8 (#133)

| Benchmark | Claude Opus 5 | Qwen3.5-Flash |
|---|---|---|
| LMArena Instruction Following | 1516 | 1374 |

## Long Context

- Claude Opus 5: 46.5 (#20)
- Qwen3.5-Flash: 42.4 (#119)

| Benchmark | Claude Opus 5 | Qwen3.5-Flash |
|---|---|---|
| LMArena Longer Query | 1516 | 1392 |

## Writing & Preference

- Claude Opus 5: 79.3 (#2)
- Qwen3.5-Flash: 58.2 (#117)

| Benchmark | Claude Opus 5 | Qwen3.5-Flash |
|---|---|---|
| LMArena Text | 1506 | 1397 |
| LMArena Creative Writing | 1491 | 1343 |
| LMArena Multi-Turn | 1496 | 1393 |
| EQ-Bench Creative Writing | 2133 | — |
| EQ-Bench 4 | 1385 | — |

## FAQ

### Is Claude Opus 5 better than Qwen3.5-Flash?

Claude Opus 5 is the stronger model overall, scoring 67.7 to 42.3 on the Noometry Index. Qwen3.5-Flash costs 57× less per token, which makes it the better buy when Claude Opus 5's lead doesn't matter for your workload.

### Which is cheaper, Claude Opus 5 or Qwen3.5-Flash?

Qwen3.5-Flash is cheaper. It lists at $0.10 per million input tokens and $0.40 per million output tokens; Claude Opus 5 lists at $5 and $25.

### Is Claude Opus 5 or Qwen3.5-Flash better for coding?

Claude Opus 5 scores higher on coding benchmarks: 67.0 versus 33.9 in the Noometry coding category.

### Which has the bigger context window?

Both accept 1M tokens.

### How many benchmarks do Claude Opus 5 and Qwen3.5-Flash share?

29 benchmarks have published results for both models. Claude Opus 5 has 57 scored results on Noometry and Qwen3.5-Flash has 32.