Claude Opus 5.5 vs Claude Sonnet 5.5
Claude Opus 5.5 Verdict
- Claude Opus 5.5 (max) leads on quality: 72.0 vs 67.6.
- Claude Opus 5.5 (max) is stronger in coding, composite, knowledge, long context, maths, multimodal.
- Claude Sonnet 5.5 (max) is stronger in agents & tools, reasoning.
- Claude Sonnet 5.5 (max) is 2.0× cheaper ($4.00 vs $8.00 per 1M blended).
- Claude Sonnet 5.5 (max) streams 1.5× faster (141 vs 96 tokens per second).
| Metric | Claude Opus 5.5 (max) | Claude Sonnet 5.5 (max) |
|---|---|---|
| BenchLeader Index | 72.0 | 67.6 |
| Agents & tools score | 69.0 | 69.5 |
| Coding score | 82.9 | 69.8 |
| Composite score | 84.7 | 72.6 |
| Knowledge score | 79.2 | 65.4 |
| Long context score | 67.6 | 66.6 |
| Maths score | 74.9 | 72.9 |
| Multimodal score | 71.1 | – |
| Reasoning score | 76.0 | 81.1 |
| Blended price $/M | $8.00 | $4.00 |
| Output speed | 96 tok/s | 141 tok/s |
| Time to first answer | 662.1 s | 487.1 s |
| Context window | 1M | 1M |
| GPQA Diamond | 90.6% | 95.6% |
| FrontierMath Tiers 1–3 | 91.2% | 88.8% |
| FrontierMath Tier 4 | 95.0% | 80.5% |
| OTIS Mock AIME | 100.0% | 100.0% |
| SimpleQA Verified | 72.2% | 46.5% |
| Terminal-Bench | 64.8% | 61.8% |
| SciCode | 66.9% | 61.0% |
| APEX-Agents | 73.5% | 75.5% |
| ProofBench | 100.0% | 100.0% |
| LMArena WebDev | 1813 | – |
| LMArena Agent | – | 12 |
| LiveBench | 83.2% | 75.7% |
| LiveBench Reasoning | 92.2% | 91.6% |
| LiveBench Coding | 89.3% | 91.4% |
| LiveBench Agentic Coding | 71.7% | 56.3% |
| LiveBench Mathematics | 97.1% | 96.1% |
| LiveBench Data Analysis | 80.3% | 59.5% |
| LiveBench Language | 86.3% | 78.0% |
| LiveBench Instruction Following | 65.7% | 56.8% |
| AA Intelligence Index v4.3.2 | 57.6 | 56 |
| AA-LCR | 84.7% | 82.7% |
| MMMU-Pro | 87.7% | – |
| AA-Omniscience | 46.4 | 32.3 |
| Humanity's Last Exam (AA) | 61.4% | 55.0% |
| SciCode (AA) | 66.9% | 61.0% |
| ARC-AGI-1 | 97.5% | – |
| ARC-AGI-2 | 91.7% | – |
| CritPt | 31.7% | 31.4% |
| GDPval-AA v2.1 | 68.3% | 67.0% |
| ITBench SRE (AA) | 38.2% | – |
| Analyst Agent (AA) | 56.3% | 57.5% |
| CUA-bench | 14.0% | – |
| EBR-bench | 71.4% | – |
| Mystery Game Puzzles | 71.0% | 65.0% |
| MirrorCode | 77.4% | – |
| LMCA | 68.2% | – |
| DTBench | 98.9% | – |
| CursorBench | 57.8% | 55.5% |
| GDP.pdf | 30.6% | – |
| FrontierSWE | 62.3% | 61.9% |
| Terminal-Bench 4.0 (AA) | 59.6% | 63.6% |
| AutomationBench | 69.5% | 71.8% |
| GDP.pdf | 26.2% | 25.8% |
| MLCR | 66.7% | 75.0% |
| Harvey LAB | 4.2% | 2.8% |
| AA-Omniscience: accuracy | 66.2% | 54.0% |
| AA-Omniscience: non-hallucination | 41.4% | 53.0% |
| AA-Briefcase v1.1 | 1807 | 1823 |
Data as of 2026-10-11. Best configuration of each model; every score links to its source on the model pages.
Claude Opus 5.5 vs Claude Sonnet 5.5: questions
- Is Claude Opus 5.5 better than Claude Sonnet 5.5?
- Claude Opus 5.5 (max) leads on quality: 72.0 vs 67.6. The BenchLeader Index combines every independent quality benchmark; Claude Opus 5.5 (max) is ahead overall as of 2026-10-11, but check the category scores for your use.
- Is Claude Opus 5.5 better than Claude Sonnet 5.5 for coding?
- Claude Opus 5.5 scores higher in coding (83 vs 70 on the category index, where 50 is average).
- Is Claude Opus 5.5 better than Claude Sonnet 5.5 for agentic tasks?
- Claude Sonnet 5.5 scores higher in agentic tasks (70 vs 69 on the category index, where 50 is average).
- Which is cheaper, Claude Opus 5.5 or Claude Sonnet 5.5?
- Claude Sonnet 5.5 is cheaper: $4.00 against $8.00 per million tokens, blended at three input tokens per output token.
- Which is faster, Claude Opus 5.5 or Claude Sonnet 5.5?
- Claude Sonnet 5.5 streams faster: 141 against 96 output tokens per second.
- Which has the larger context window?
- Both accept 1M tokens of context.