Claude Opus 5.5 vs Qwen3.8 27B
| Spec | Claude Opus 5.5 | Qwen3.8 27B |
|---|---|---|
| Respan Index | 73.7 (#1) | 42.1 (#54) |
| Blended price per 1M | $4 | $0.154 |
| Context window | 1M | 262K |
| Input / output per 1M | $2 / $10 | $0.039 / $0.5 |
| Max output | 128K | - |
| Input | text, vision | text, vision |
| Released | 2026-09-22 | 2026-08-14 |
Respan Index by category
Each category is scored 0 to 100, and how far ahead the winner is. Leads under a point are close to even.
| Category | Claude Opus 5.5 | Qwen3.8 27B |
|---|---|---|
| Coding | 66.8 Claude Opus 5.5 | 23.6 Qwen3.8 27B |
| Agents | 79.2 Claude Opus 5.5 | 56.1 Qwen3.8 27B |
| Reasoning | 83.9 Claude Opus 5.5 | 39.3 Qwen3.8 27B |
| Knowledge & language | 70.4 Claude Opus 5.5 | 40.5 Qwen3.8 27B |
| Human preference | 61.4 Claude Opus 5.5 | 55.4 Qwen3.8 27B |
Benchmarks both report
Claude Opus 5.5 leads on 13 of the 15 benchmarks both report. Higher is better. Each score links to where it was published.
| Benchmark | Claude Opus 5.5 | Qwen3.8 27B |
|---|---|---|
| LMArena Agent (LMArena) | 0.2094 | -0.0446 |
| LMArena Elo | 1509 | 1436 |
| LMArena WebDev (LMArena) | 1810 | 1590 |
| LMArena Vision (LMArena) | 1293 | 1242 |
| APEX-Agents (Mercor) | 73.5% | 47.5% |
| GPQA Diamond | 90.6% | 89.2% |
| LiveBench Agentic Coding (LiveBench) | 71.7% | 61.4% |
| LiveBench Coding (LiveBench) | 89.3% | 75.7% |
| LiveBench Data Analysis (LiveBench) | 80.3% | 76.6% |
| LiveBench Instruction Following (LiveBench) | 67% | 72.7% |
| LiveBench Language (LiveBench) | 86.3% | 74.3% |
| LiveBench Mathematics (LiveBench) | 97.1% | 86.2% |
| LiveBench Reasoning (LiveBench) | 92.2% | 80% |
| SAGE (Vals AI) | 45.8% | 52.4% |
| SimpleBench (SimpleBench) | 88.4% | 60.2% |
FAQ
Is Claude Opus 5.5 better than Qwen3.8 27B?
Claude Opus 5.5 scores 73.7 on the Respan Index (#1), ahead of Qwen3.8 27B at 42.1 (#54). Claude Opus 5.5 leads on 13 of the 15 benchmarks both report.
Which is cheaper, Claude Opus 5.5 or Qwen3.8 27B?
Claude Opus 5.5 lists at $2 input and $10 output per 1M tokens; Qwen3.8 27B at $0.039 and $0.5. Qwen3.8 27B is 26x cheaper per token at list price.
Which has the larger context window?
Claude Opus 5.5 accepts 1M tokens and Qwen3.8 27B 262K tokens.