Compare / head-to-head
GPT-5.1vsQwen3.5-Flash
GPT-5.1 leads 4 of 4 shared benchmarks. Qwen3.5-Flash is 35.6x cheaper per token. Qwen3.5-Flash has the larger context window (1M tokens).
Benchmarks from cited public sources; pricing from official pages; status from official provider feeds.
Shared benchmarks
4 – 0
GPT-5.1 leads
Cheaper per token
Qwen3.5-Flash
35.6x cheaper, input + output
Larger context
Qwen3.5-Flash
1M tokens
Provider uptime (30d)
95.2941% · —
OpenAI · Qwen
GPT-5.1
OpenAI · released 2025-11-13
textvision
Qwen3.5-Flash
Qwen · released 2026-02-23
textvision
Quality
Benchmark matrix
4 shared · 2 only GPT-5.1 · 1 only Qwen3.5-Flash| Benchmark | GPT-5.1 | Qwen3.5-Flash | Δ | Edge |
|---|---|---|---|---|
| Reported by both · 4 | ||||
| GPQA Diamond | 87.6% ↗epoch | 82.3% ↗epoch | +5.3 pt | GPT-5.1 |
| LMArena Elo | 1422.6 ↗ | 1397.7 ↗ | +24.9 | GPT-5.1 |
| OTIS Mock AIME 2024-2025 (Epoch AI run) | 88.6% ↗epoch | 84.4% ↗epoch | +4.2 pt | GPT-5.1 |
| SimpleQA Verified | 48% ↗epoch | 20.3% ↗epoch | +27.7 pt | GPT-5.1 |
| Only GPT-5.1 reports · 2 | ||||
| AIME 2025 | 94.2% ↗matharena ⚠ | not reported | — | — |
| SWE-bench Verified (Epoch AI run) | 68% ↗epoch | not reported | — | — |
| Only Qwen3.5-Flash reports · 1 | ||||
| FrontierMath Tiers 1-3 v2 (Epoch AI run) | not reported | 9.5% ↗epoch | — | — |
Scores tagged "epoch" or "matharena" are independent runs, used only where the lab has not published its own; ⚠ marks rows MathArena flags as released after the competition. Higher is better on every row. Δ is GPT-5.1 minus Qwen3.5-Flash in the benchmark's own unit. "Not reported" means the lab has not published that figure; it is not a zero. ↗ opens the source.
Specs & pricing
Side by side
Official pricing pages and model cards| Spec | GPT-5.1 | Qwen3.5-Flash | Edge |
|---|---|---|---|
| Context window | 400K tokens | 1M tokens | Qwen3.5-Flash |
| Max output | 128K tokens | — | — |
| Input price / 1M | $1.25 ↗ | $0.029 ↗ | Qwen3.5-Flash |
| Output price / 1M | $10 ↗ | $0.287 ↗ | Qwen3.5-Flash |
| Cached input / 1M | $0.125 ↗ | — | — |
| Input + output / 1M Lower is cheaper. List prices; batch, tool and regional fees excluded. | $11.25 | $0.316 | Qwen3.5-Flash |
| Modalities | text · vision | text · vision | Tie |
| Released | 2025-11-13 | 2026-02-23 | — |
| Cited benchmark scores | 6 | 5 | — |
Reliability
Provider status
Last 60 days · refreshed daily on this page · live on /statusMore matchups
GPT-5.1 vs …
Models sharing the most benchmarksMore matchups
Qwen3.5-Flash vs …
Models sharing the most benchmarksBuilt by Respan
Which one wins on your data?
Public benchmarks are a starting point. Run GPT-5.1 and Qwen3.5-Flash on your own prompts with Respan evals, or route to either through one gateway key with automatic failover.