Claude Opus 4.8 vs GPT-6 Astra
Claude Opus 4.8 
GPT-6 Astra Verdict
- GPT-6 Astra (max) leads on quality: 70.6 vs 64.7.
- Claude Opus 4.8 is stronger in composite, human preference, instruction following, long context, multimodal.
- GPT-6 Astra (max) is stronger in agents & tools, coding, knowledge, reasoning, maths.
- Claude Opus 4.8 is 2.2× cheaper ($10.00 vs $22.00 per 1M blended).
| Metric | Claude Opus 4.8 | GPT-6 Astra (max) |
|---|---|---|
| BenchLeader Index | 64.7 | 70.6 |
| Agents & tools score | 65.0 | 68.2 |
| Coding score | 65.7 | 79.0 |
| Composite score | 81.9 | 73.1 |
| Human preference score | 65.6 | – |
| Instruction following score | 61.6 | – |
| Knowledge score | 66.3 | 79.8 |
| Long context score | 65.3 | – |
| Multimodal score | 64.4 | – |
| Reasoning score | 64.2 | 70.9 |
| Maths score | – | 77.0 |
| Blended price $/M | $10.00 | $22.00 |
| Output speed | 58 tok/s | 54 tok/s |
| Time to first answer | 29.5 s | 328.6 s |
| Context window | 1M | 1.1M |
| GPQA Diamond | – | 95.8% |
| FrontierMath Tiers 1–3 | – | 93.7% |
| FrontierMath Tier 4 | – | 97.6% |
| OTIS Mock AIME | – | 100.0% |
| SimpleQA Verified | – | 75.6% |
| Terminal-Bench | – | 58.2% |
| SimpleBench | 64.8% | – |
| SciCode | – | 56.5% |
| Remote Labor Index | 8.3% | – |
| FrontierCode | 46.5% | 53.3% |
| GSO-Bench | 47.1% | – |
| Epoch Capabilities Index | 158.3 | – |
| LMArena Text | 1473 | – |
| LMArena Hard Prompts | 1503 | – |
| LMArena Coding | 1527 | – |
| LMArena WebDev | 1540 | 1796 |
| LMArena Vision | 1289 | – |
| LMArena Agent | – | 12.5 |
| LiveBench | – | 82.2% |
| LiveBench Reasoning | – | 92.7% |
| LiveBench Coding | – | 80.4% |
| LiveBench Agentic Coding | – | 57.3% |
| LiveBench Mathematics | – | 96.8% |
| LiveBench Data Analysis | – | 83.0% |
| LiveBench Language | – | 89.4% |
| AA Intelligence Index | 42.0 | – |
| IFBench | 62.2% | – |
| AA-LCR | 77.7% | – |
| AA-Omniscience | 28.8 | – |
| Terminal-Bench Hard | 58.3% | – |
| GPQA Diamond (AA) | 92.0% | – |
| Humanity's Last Exam (AA) | 48.7% | – |
| SciCode (AA) | 54.4% | – |
| τ²-Bench Telecom (AA) | 94.4% | – |
| LiveCodeBench | 87.8% | – |
| MMLU-Pro | 89.6% | – |
| LegalBench | 83.6% | – |
| CorpFin | 66.7% | – |
| TaxEval | 75.6% | – |
| Terminal-Bench 2.1 (Vals) | 71.9% | 87.3% |
| SWE-bench (Vals) | 88.6% | – |
| GPQA Diamond (Vals) | 92.4% | – |
| Vals Index | 60.9 | 66.6 |
| HiL-Bench | 35.3% | – |
| EQ-Bench 4 | 1281 | – |
| ARC-AGI-1 | – | 97.5% |
| ARC-AGI-2 | – | 95.0% |
| ARC-AGI-3 | – | 62.7% |
Data as of 2026-09-09. Best configuration of each model; every score links to its source on the model pages.