Claude Opus 5 vs Claude Opus 5.5
Claude Opus 5 Verdict
- Claude Opus 5 (high) and Claude Opus 5.5 (thinking) are level on quality (69.8 vs 70.7).
- Claude Opus 5 (high) is stronger in agents & tools, coding, human preference, maths.
- Claude Opus 5.5 (thinking) is stronger in composite, knowledge, long context, multimodal, reasoning.
- Claude Opus 5.5 (thinking) is 1.3× cheaper ($8.00 vs $10.00 per 1M blended).
| Metric | Claude Opus 5 (high) | Claude Opus 5.5 (thinking) |
|---|---|---|
| BenchLeader Index | 69.8 | 70.7 |
| Agents & tools score | 66.0 | – |
| Coding score | 71.4 | – |
| Composite score | 87.9 | 95.0 |
| Human preference score | 69.8 | – |
| Knowledge score | 79.1 | 85.0 |
| Long context score | 65.6 | 68.5 |
| Maths score | 72.3 | – |
| Multimodal score | 67.3 | 71.9 |
| Reasoning score | 75.2 | 95.0 |
| Blended price $/M | $10.00 | $8.00 |
| Output speed | 55 tok/s | 48 tok/s |
| Time to first answer | 16.1 s | 4.2 s |
| Context window | 1M | 1M |
| 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 | 48.1 | 57.6 |
| AA-LCR | 79.0% | 84.7% |
| MMMU-Pro | 82.4% | 87.7% |
| AA-Omniscience | 33.7 | 46.4 |
| GPQA Diamond (AA) | 93.7% | – |
| Humanity's Last Exam (AA) | 52.8% | 61.4% |
| SciCode (AA) | 55.4% | 66.9% |
| ARC-AGI-1 | 97.5% | – |
| ARC-AGI-2 | 88.3% | – |
| ARC-AGI-3 | 30.2% | – |
| CritPt | 28.3% | 31.7% |
| GDPval (AA) | 54.0% | 67.3% |
| 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 | 63.7% | – |
| DTBench | 97.9% | – |
| CursorBench | 44.7% | – |
| ALE-Bench | 2164.6 | – |
| Terminal-Bench 4.0 (AA) | 46.0% | 59.6% |
| Terminal-Bench 2.1 (AA) | 87.6% | – |
| AutomationBench | 53.6% | 69.5% |
| GDP.pdf | 19.6% | 26.2% |
| MLCR | 59.4% | – |
| Harvey LAB | – | 91.2% |
| AA-Omniscience: accuracy | 58.9% | 66.2% |
| AA-Omniscience: non-hallucination | 38.8% | 41.4% |
| AA-Briefcase | 1573 | 1822 |
Data as of 2026-09-22. Best configuration of each model; every score links to its source on the model pages.
Claude Opus 5 vs Claude Opus 5.5: questions
- Is Claude Opus 5 better than Claude Opus 5.5?
- Claude Opus 5 (high) and Claude Opus 5.5 (thinking) are level on quality (69.8 vs 70.7). The BenchLeader Index combines every independent quality benchmark; Claude Opus 5.5 (thinking) is ahead overall as of 2026-09-22, but check the category scores for your use.
- Which is cheaper, Claude Opus 5 or Claude Opus 5.5?
- Claude Opus 5.5 is cheaper: $8.00 against $10.00 per million tokens, blended at three input tokens per output token.
- Which is faster, Claude Opus 5 or Claude Opus 5.5?
- Claude Opus 5 streams faster: 55 against 48 output tokens per second.
- Which has the larger context window?
- Both accept 1M tokens of context.