Model comparison
GPT-5.5 Pro 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: GPT-5.5 Pro #38 (Estimated); Qwen3.5 Flash #134 (Supported). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.
Evidence parity. GPT-5.5 Pro and Qwen3.5 Flash share 2 comparable benchmark results. 1 of 8 categories are comparable. 5 results are unique to GPT-5.5 Pro; 0 to Qwen3.5 Flash.
Updated July 22, 2026- Shared results
- 2
- GPT-5.5 Pro only
- 5
- Qwen3.5 Flash only
- 0
- Comparable categories
- 1 / 8
Pick GPT-5.5 Pro if you want the stronger benchmark profile. Qwen3.5 Flash only becomes the better choice if 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
GPT-5.5 Pro is clearly ahead on the BenchAlign aggregate, 63.69 to 47.65. The gap is large enough that you do not need to squint at the spreadsheet to see the difference.
GPT-5.5 Pro's sharpest advantage is in mathematics, where it averages 48.1 against 4.7. The single biggest benchmark swing on the page is FrontierMath v2 (Tiers 1-3), 51.000% to 6.207%.
GPT-5.5 Pro is also the more expensive model on tokens at $30.00 input / $180.00 output per 1M tokens, versus $0.10 input / $0.40 output per 1M tokens for Qwen3.5 Flash. That is roughly 450.0x on output cost alone.
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 | GPT-5.5 Pro | Δ | Qwen3.5 Flash |
|---|---|---|---|
| Math | GPT-5.5 Pro48.1 | Margin← 43.4 | Qwen3.5 Flash4.7 |
| Agentic | GPT-5.5 Pro90.1 | MarginNo overlap | Qwen3.5 FlashNot measured |
| Knowledge | GPT-5.5 Pro57.2 | 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 51.000%B 6.207%Winner: GPT-5.5 ProΔ 44.8FrontierMath v2 (Tiers 1-3): GPT-5.5 Pro scored 51.000%; Qwen3.5 Flash scored 6.207%. GPT-5.5 Pro wins this benchmark. - Source ↗
FrontierMath v2 (Tier 4)
MathA 39.600%B 0.000%Winner: GPT-5.5 ProΔ 39.6FrontierMath v2 (Tier 4): GPT-5.5 Pro scored 39.600%; Qwen3.5 Flash scored 0.000%. GPT-5.5 Pro wins this benchmark.
Operational comparison
Runtime and commercial metrics are compared only when both models have a complete sourced value.
| Metric | GPT-5.5 Pro | Qwen3.5 Flash | Comparison |
|---|---|---|---|
| Input / output priceUSD per 1M tokens | GPT-5.5 Pro$30 input / $180 output | Qwen3.5 Flash$0.1 input / $0.4 output | Qwen3.5 Flash has the lower combined listed price. |
| Generation speedtokens per second | GPT-5.5 ProNot available | Qwen3.5 FlashNot available | A complete speed comparison is not available. |
| First-answer latencyseconds to first token | GPT-5.5 ProNot available | Qwen3.5 FlashNot available | A complete latency comparison is not available. |
| Context windowmaximum listed tokens | GPT-5.5 Pro1M | Qwen3.5 Flash1M | Listed context windows are equal. |
Benchmark Deep Dive
Frequently Asked Questions (2)
Which is better, GPT-5.5 Pro or Qwen3.5 Flash?
GPT-5.5 Pro is ahead on BenchLM's BenchAlign leaderboard, 63.69 to 47.65. The biggest single separator in this matchup is FrontierMath v2 (Tiers 1-3), where the scores are 51.000% and 6.207%.
Which is better for math, GPT-5.5 Pro or Qwen3.5 Flash?
GPT-5.5 Pro has the edge for math in this comparison, averaging 48.1 versus 4.7. Inside this category, FrontierMath v2 (Tiers 1-3) is the benchmark that creates the most daylight between them.
Related Comparisons
Explore More
Choose a model with this week’s evidence
Join 2,000+ readers for ranking moves, pricing changes, and the claims that still need proof.
One email each week. Unsubscribe anytime.