Model comparison
Claude 3.5 Sonnet vs Qwen3.5 Flash
Head-to-head evidence from 2 shared benchmark results across 1 category. Overall scores shown here use the public BenchAlign v5 ranking lane.
Public leaderboard positions: Claude 3.5 Sonnet #132 (Estimated); Qwen3.5 Flash #134 (Supported). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.
Evidence parity. Claude 3.5 Sonnet and Qwen3.5 Flash share 2 comparable benchmark results. 1 of 8 categories are comparable. 2 results are unique to Claude 3.5 Sonnet; 0 to Qwen3.5 Flash.
Updated July 23, 2026- Shared results
- 2
- Claude 3.5 Sonnet only
- 2
- Qwen3.5 Flash only
- 0
- Comparable categories
- 1 / 8
Pick Claude 3.5 Sonnet if you want the stronger benchmark profile. Qwen3.5 Flash only becomes the better choice if mathematics is the priority or you want the cheaper token bill.
Confidence note. This is a partial-evidence comparison with 2 shared benchmark results across 1 evidence category; 1 of 8 categories currently have scoreable aggregates for both models. Treat the verdict as directional until coverage is more balanced.
Why this result
Claude 3.5 Sonnet has the cleaner BenchAlign overall profile here, landing at 47.74 versus 47.65. It is a real lead, but still close enough that category-level strengths matter more than the headline number.
Claude 3.5 Sonnet is also the more expensive model on tokens at $3.00 input / $15.00 output per 1M tokens, versus $0.10 input / $0.40 output per 1M tokens for Qwen3.5 Flash. That is roughly 37.5x on output cost alone. Qwen3.5 Flash is the reasoning model in the pair, while Claude 3.5 Sonnet is not. That usually helps on harder chain-of-thought-heavy tests, but it can also mean more latency and more token spend in real use. Qwen3.5 Flash gives you the larger context window at 1M, compared with 200K for Claude 3.5 Sonnet.
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 | Claude 3.5 Sonnet | Δ | Qwen3.5 Flash |
|---|---|---|---|
| Math | Claude 3.5 Sonnet1.6 | Margin→ 3.1 | Qwen3.5 Flash4.7 |
| Coding | Claude 3.5 Sonnet49.0 | MarginNo overlap | Qwen3.5 FlashNot measured |
| Knowledge | Claude 3.5 Sonnet59.4 | MarginNo overlap | Qwen3.5 FlashNot measured |
Decisive benchmark drivers
The largest measured benchmark gaps in this matchup, with exact reported values.
More
- Source ↗
FrontierMath v2 (Tiers 1-3)
MathA 2.069%B 6.207%Winner: Qwen3.5 FlashΔ 4.1FrontierMath v2 (Tiers 1-3): Claude 3.5 Sonnet scored 2.069%; Qwen3.5 Flash scored 6.207%. Qwen3.5 Flash wins this benchmark.
Operational comparison
Runtime and commercial metrics are compared only when both models have a complete sourced value.
| Metric | Claude 3.5 Sonnet | Qwen3.5 Flash | Comparison |
|---|---|---|---|
| Input / output priceUSD per 1M tokens | Claude 3.5 Sonnet$3 input / $15 output | Qwen3.5 Flash$0.1 input / $0.4 output | Qwen3.5 Flash has the lower combined listed price. |
| Generation speedtokens per second | Claude 3.5 SonnetNot available | Qwen3.5 FlashNot available | A complete speed comparison is not available. |
| First-answer latencyseconds to first token | Claude 3.5 SonnetNot available | Qwen3.5 FlashNot available | A complete latency comparison is not available. |
| Context windowmaximum listed tokens | Claude 3.5 Sonnet200K | Qwen3.5 Flash1M | Qwen3.5 Flash lists the larger context window. |
Benchmark Deep Dive
Frequently Asked Questions (2)
Which is better, Claude 3.5 Sonnet or Qwen3.5 Flash?
Claude 3.5 Sonnet is ahead on BenchLM's BenchAlign leaderboard, 47.74 to 47.65. The biggest single separator in this matchup is FrontierMath v2 (Tiers 1-3), where the scores are 2.069% and 6.207%.
Which is better for math, Claude 3.5 Sonnet or Qwen3.5 Flash?
Qwen3.5 Flash has the edge for math in this comparison, averaging 4.7 versus 1.6. Inside this category, FrontierMath v2 (Tiers 1-3) is the benchmark that creates the most daylight between them.
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