Claude Opus 5 vs GPT-5.5 Pro
Claude Opus 5 
GPT-5.5 Pro Verdict
- Claude Opus 5 (high) leads on quality: 70.2 vs 67.1.
- Claude Opus 5 (high) is stronger in agents & tools, coding, composite, human preference, knowledge, long context, multimodal.
- GPT-5.5 Pro (xhigh) is stronger in maths, reasoning.
- Claude Opus 5 (high) is 6.8× cheaper ($10.00 vs $67.50 per 1M blended).
- Claude Opus 5 (high) streams 13.4× faster (54 vs 4 tokens per second).
| Metric | Claude Opus 5 (high) | GPT-5.5 Pro (xhigh) |
|---|---|---|
| BenchLeader Index | 70.2 | 67.1 |
| Agents & tools score | 66.0 | – |
| Coding score | 71.9 | – |
| Composite score | 90.2 | – |
| Human preference score | 69.7 | – |
| Knowledge score | 80.3 | – |
| Long context score | 65.9 | – |
| Maths score | 72.3 | 74.5 |
| Multimodal score | 67.6 | – |
| Reasoning score | 75.6 | 80.1 |
| Blended price $/M | $10.00 | $67.50 |
| Output speed | 54 tok/s | 4 tok/s |
| Time to first answer | 16.7 s | 3.5 s |
| Context window | 1M | 1.1M |
| FrontierMath Tiers 1–3 | – | 87.7% |
| FrontierMath Tier 4 | – | 78.0% |
| Terminal-Bench | 50.3% | – |
| OSWorld-Verified 2.0 | 29.0% | – |
| SciCode | 54.3% | – |
| WeirdML | 91.6% | – |
| LMArena Text | 1493 | – |
| LMArena Hard Prompts | 1517 | – |
| LMArena Coding | 1533 | – |
| LMArena WebDev | 1660 | – |
| LMArena Vision | 1321 | – |
| LMArena Agent | 10.2 | – |
| AA Intelligence Index | 48.2 | – |
| AA-LCR | 79.0% | – |
| MMMU-Pro | 82.4% | – |
| AA-Omniscience | 33.7 | – |
| GPQA Diamond (AA) | 93.7% | – |
| Humanity's Last Exam (AA) | 52.8% | – |
| SciCode (AA) | 55.4% | – |
| ARC-AGI-1 | 97.5% | 95.0% |
| ARC-AGI-2 | 88.3% | 84.2% |
| ARC-AGI-3 | 30.2% | – |
| CritPt | 28.3% | 30.6% |
| GDPval (AA) | 56.5% | – |
| τ²-Bench Banking (AA) | 44.7% | – |
| LMArena Maths | 1525 | – |
| LMArena Creative Writing | 1474 | – |
| LMArena Instruction Following | 1499 | – |
| LMArena Multi-turn | 1484 | – |
| LMArena Longer Queries | 1508 | – |
| LMArena Document | 1490 | – |
| DeepSWE | 72.8% | – |
| LMCA | – | 53.9% |
| DTBench | – | 96.0% |
| CursorBench | 66.7% | – |
| ALE-Bench | 2164.6 | – |
Data as of 2026-09-19. Best configuration of each model; every score links to its source on the model pages.
Claude Opus 5 vs GPT-5.5 Pro: questions
- Is Claude Opus 5 better than GPT-5.5 Pro?
- Claude Opus 5 (high) leads on quality: 70.2 vs 67.1. The BenchLeader Index combines every independent quality benchmark; Claude Opus 5 (high) is ahead overall as of 2026-09-19, but check the category scores for your use.
- Which is cheaper, Claude Opus 5 or GPT-5.5 Pro?
- Claude Opus 5 is cheaper: $10.00 against $67.50 per million tokens, blended at three input tokens per output token.
- Which is faster, Claude Opus 5 or GPT-5.5 Pro?
- Claude Opus 5 streams faster: 54 against 4 output tokens per second.
- Which has the larger context window?
- GPT-5.5 Pro accepts more context: 1.1M against 1M tokens.