Claude Opus 5.5 vs GPT-5.2
Claude Opus 5.5 
GPT-5.2 Verdict
- Claude Opus 5.5 (thinking) leads on quality: 70.7 vs 61.5.
- Claude Opus 5.5 (thinking) is stronger in composite, knowledge, long context, multimodal, reasoning.
- GPT-5.2 (xhigh) is stronger in agents & tools, coding, instruction following, maths.
- GPT-5.2 (xhigh) is 1.7× cheaper ($4.81 vs $8.00 per 1M blended).
- GPT-5.2 (xhigh) streams 1.7× faster (81 vs 48 tokens per second).
| Metric | Claude Opus 5.5 (thinking) | GPT-5.2 (xhigh) |
|---|---|---|
| BenchLeader Index | 70.7 | 61.5 |
| Composite score | 95.0 | 66.3 |
| Knowledge score | 85.0 | 57.7 |
| Long context score | 68.5 | 67.5 |
| Multimodal score | 71.9 | – |
| Reasoning score | 95.0 | 62.4 |
| Agents & tools score | – | 54.8 |
| Coding score | – | 63.0 |
| Instruction following score | – | 73.4 |
| Maths score | – | 58.4 |
| Blended price $/M | $8.00 | $4.81 |
| Output speed | 48 tok/s | 81 tok/s |
| Time to first answer | 4.2 s | 185.6 s |
| Context window | 1M | 400k |
| GPQA Diamond | – | 91.4% |
| FrontierMath Tiers 1–3 | – | 67.4% |
| FrontierMath Tier 4 | – | 31.7% |
| OTIS Mock AIME | – | 96.1% |
| SimpleQA Verified | – | 37.1% |
| WeirdML | – | 72.2% |
| ProofBench | – | 15.0% |
| AA Intelligence Index | 57.6 | 30.4 |
| IFBench | – | 75.4% |
| AA-LCR | 84.7% | 82.7% |
| MMMU-Pro | 87.7% | – |
| AA-Omniscience | 46.4 | -0.9 |
| Terminal-Bench Hard | – | 47.0% |
| GPQA Diamond (AA) | – | 90.3% |
| Humanity's Last Exam (AA) | 61.4% | 37.7% |
| SciCode (AA) | 66.9% | – |
| τ²-Bench Telecom (AA) | – | 84.8% |
| AIME (Vals) | – | 96.9% |
| LiveCodeBench | – | 85.4% |
| MMLU-Pro | – | 86.2% |
| LegalBench | – | 82.8% |
| CorpFin | – | 65.9% |
| TaxEval | – | 75.8% |
| MedQA | – | 94.1% |
| MGSM | – | 94.0% |
| SWE-bench (Vals) | – | 75.8% |
| GPQA Diamond (Vals) | – | 91.7% |
| MCP Atlas | – | 67.6% |
| ARC-AGI-1 | – | 86.2% |
| ARC-AGI-2 | – | 52.9% |
| CritPt | 31.7% | 11.6% |
| GDPval (AA) | 67.3% | – |
| CaseLaw v2 | – | 66.0% |
| MedCode | – | 49.8% |
| MedScribe | – | 84.4% |
| MMMU-Pro (Vals) | – | 86.7% |
| MortgageTax | – | 67.1% |
| SAGE | – | 49.3% |
| Vibe Code Bench v1.1 | – | 53.5% |
| DrugDiscoveryBench | – | 29.3% |
| Chess Puzzles | – | 49.0% |
| EBR-bench | – | 23.0% |
| VPCT | – | 84.0% |
| LMCA | – | 43.9% |
| DTBench | – | 90.9% |
| Terminal-Bench 4.0 (AA) | 59.6% | – |
| AutomationBench | 69.5% | – |
| GDP.pdf | 26.2% | – |
| Harvey LAB | 91.2% | – |
| AA-Omniscience: accuracy | 66.2% | 44.3% |
| AA-Omniscience: non-hallucination | 41.4% | 18.8% |
| AA-Briefcase | 1822 | – |
Data as of 2026-09-22. Best configuration of each model; every score links to its source on the model pages.
Claude Opus 5.5 vs GPT-5.2: questions
- Is Claude Opus 5.5 better than GPT-5.2?
- Claude Opus 5.5 (thinking) leads on quality: 70.7 vs 61.5. 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 5.5 or GPT-5.2?
- GPT-5.2 is cheaper: $4.81 against $8.00 per million tokens, blended at three input tokens per output token.
- Which is faster, Claude Opus 5.5 or GPT-5.2?
- GPT-5.2 streams faster: 81 against 48 output tokens per second.
- Which has the larger context window?
- Claude Opus 5.5 accepts more context: 1M against 400k tokens.