Model comparison
GPT-5.1 vs Qwen3.5 397B
Head-to-head evidence from 17 shared benchmark results across 6 categories. Overall scores shown here use the public BenchAlign v5 ranking lane.
Public leaderboard positions: GPT-5.1 #94 (Estimated); Qwen3.5 397B #71 (Estimated). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.
Evidence parity. GPT-5.1 and Qwen3.5 397B share 17 comparable benchmark results. 1 of 8 categories are comparable. 4 results are unique to GPT-5.1; 38 to Qwen3.5 397B.
Updated July 20, 2026- Shared results
- 17
- GPT-5.1 only
- 4
- Qwen3.5 397B only
- 38
- Comparable categories
- 1 / 8
Pick Qwen3.5 397B if you want the stronger benchmark profile. GPT-5.1 only becomes the better choice if you need the larger 200K context window or you want the stronger reasoning-first profile.
Confidence note. This is a partial-evidence comparison with 17 shared benchmark results across 6 evidence categories; 1 of 8 categories currently have scoreable aggregates for both models. Treat the verdict as directional until coverage is more balanced.
Why this result
Qwen3.5 397B is clearly ahead on the BenchAlign aggregate, 57.01 to 53.65. The gap is large enough that you do not need to squint at the spreadsheet to see the difference.
Qwen3.5 397B's sharpest advantage is in mathematics, where it averages 90.6 against 26.4.
GPT-5.1 is also the more expensive model on tokens at $1.25 input / $10.00 output per 1M tokens, versus $0.60 input / $3.60 output per 1M tokens for Qwen3.5 397B. That is roughly 2.8x on output cost alone. GPT-5.1 is the reasoning model in the pair, while Qwen3.5 397B 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. GPT-5.1 gives you the larger context window at 200K, compared with 128K for Qwen3.5 397B.
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-5.1 | Δ | Qwen3.5 397B |
|---|---|---|---|
| Math | GPT-5.126.4 | Margin→ 64.2 | Qwen3.5 397B90.6 |
| Agentic | GPT-5.1Not measured | MarginNo overlap | Qwen3.5 397B56.5 |
| Coding | GPT-5.1Not measured | MarginNo overlap | Qwen3.5 397B66.5 |
| Reasoning | GPT-5.1Not measured | MarginNo overlap | Qwen3.5 397B63.2 |
| Knowledge | GPT-5.1Not measured | MarginNo overlap | Qwen3.5 397B56.6 |
| Multilingual | GPT-5.1Not measured | MarginNo overlap | Qwen3.5 397B84.7 |
| Multimodal | GPT-5.1Not measured | MarginNo overlap | Qwen3.5 397B79.6 |
| Inst. Following | GPT-5.1Not measured | MarginNo overlap | Qwen3.5 397B92.6 |
Operational comparison
Runtime and commercial metrics are compared only when both models have a complete sourced value.
| Metric | GPT-5.1 | Qwen3.5 397B | Comparison |
|---|---|---|---|
| Input / output priceUSD per 1M tokens | GPT-5.1$1.25 input / $10 output | Qwen3.5 397B$0.6 input / $3.6 output | Qwen3.5 397B has the lower combined listed price. |
| Generation speedtokens per second | GPT-5.1111 tok/s | Qwen3.5 397B96 tok/s | GPT-5.1 has the higher measured throughput. |
| First-answer latencyseconds to first token | GPT-5.157.47 s | Qwen3.5 397B2.44 s | Qwen3.5 397B reaches the first token sooner. |
| Context windowmaximum listed tokens | GPT-5.1200K | Qwen3.5 397B128K | GPT-5.1 lists the larger context window. |
Benchmark Deep Dive
Agentic18 benchmarks
| Benchmark | GPT-5.1 | Qwen3.5 397B | Result |
|---|---|---|---|
| AA Agentic IndexSource | 21.0% | 19.9% | GPT-5.1 leads |
| τ²-bench resultsSource | 81.9% | 95.6% | Qwen3.5 397B leads |
| Gert LabsSource | 41.24% | 46.76% | Qwen3.5 397B leads |
| GDPval-AASource | 24.4% | 23.1% | GPT-5.1 leads |
| GDPval-AASource | 987 | 962 | GPT-5.1 leads |
| Terminal-Bench 2.0Source | — | 52.5% | Not comparable |
| BrowseCompSource | — | 62% | Not comparable |
| Claw-EvalSource | — | 56.8% | Not comparable |
| QwenClawBenchSource | — | 51.8% | Not comparable |
| τ³-bench resultsSource | — | 68.4% | Not comparable |
| VITA-BenchSource | — | 43.7% | Not comparable |
| DeepPlanningSource | — | 37.6% | Not comparable |
| ToolathlonSource | — | 36.3% | Not comparable |
| MCP AtlasSource | — | 46.1% | Not comparable |
| MCP-TasksSource | — | 74.2% | Not comparable |
| WideResearchSource | — | 74.0% | Not comparable |
| ResearchClawBenchSource | — | 14.2% | Not comparable |
| APEX-Agents-AASource | — | 15.3% | Not comparable |
Coding6 benchmarks
Reasoning4 benchmarks
Knowledge12 benchmarks
| Benchmark | GPT-5.1 | Qwen3.5 397B | Result |
|---|---|---|---|
| Artificial Analysis Intelligence IndexSource | 36.9% | 33.7% | GPT-5.1 leads |
| AA-GPQA DiamondSource | 87.3% | 89.3% | Qwen3.5 397B leads |
| AA-HLESource | 26.5% | 27.3% | Qwen3.5 397B leads |
| AA-Omniscience IndexSource | 5.6% | -29.8% | GPT-5.1 leads |
| AA-Omniscience AccuracySource | 37.6% | 31.4% | GPT-5.1 leads |
| AA-Omniscience Hallucination RateSource | 51.3% | 89.1% | GPT-5.1 leads |
| GPQASource | — | 88.4% | Not comparable |
| SuperGPQASource | — | 70.4% | Not comparable |
| MMLU-ProSource | — | 87.8% | Not comparable |
| MMLU-ReduxSource | — | 94.9% | Not comparable |
| C-EvalSource | — | 93% | Not comparable |
| HLESource | — | 28.7% | Not comparable |
MathQwen3.5 397B wins7 benchmarks
| Benchmark | GPT-5.1 | Qwen3.5 397B | Result |
|---|---|---|---|
| FrontierMath v2 (Tiers 1-3)Source | 31.034% | — | Not comparable |
| FrontierMath v2 (Tier 4)Source | 12.500% | — | Not comparable |
| AIME26Source | — | 93.3% | Not comparable |
| HMMT Feb 2025Source | — | 94.8% | Not comparable |
| HMMT Nov 2025Source | — | 92.7% | Not comparable |
| HMMT Feb 2026Source | — | 87.9% | Not comparable |
| MMAnswerBenchSource | — | 80.9% | Not comparable |
Multilingual2 benchmarks
Multimodal8 benchmarks
| Benchmark | GPT-5.1 | Qwen3.5 397B | Result |
|---|---|---|---|
| AA-MMMU-ProSource | 75.5% | 77.3% | Qwen3.5 397B leads |
| Design Arena WebsiteSource | 1220 | — | Not comparable |
| MMMU-ProSource | — | 79% | Not comparable |
| MathVisionSource | — | 88.6% | Not comparable |
| CharXivSource | — | 80.8% | Not comparable |
| VideoMMMUSource | — | 84.7% | Not comparable |
| ScreenSpot ProSource | — | 65.6% | Not comparable |
| V*Source | — | 95.8% | Not comparable |
Frequently Asked Questions (2)
Which is better, GPT-5.1 or Qwen3.5 397B?
Qwen3.5 397B is ahead on BenchLM's BenchAlign leaderboard, 57.01 to 53.65.
Which is better for math, GPT-5.1 or Qwen3.5 397B?
Qwen3.5 397B has the edge for math in this comparison, averaging 90.6 versus 26.4. GPT-5.1 stays close enough that the answer can still flip depending on your workload.
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