Claude Opus 4.5 vs Grok 4
Claude Opus 4.5 
Grok 4 Verdict
- Claude Opus 4.5 (thinking) and Grok 4 are level on quality (59.4 vs 59.8).
- Claude Opus 4.5 (thinking) is stronger in agents & tools, composite, knowledge, maths, multimodal, reasoning.
- Grok 4 is stronger in coding, instruction following, long context, human preference.
- Grok 4 is 6.4× cheaper ($1.56 vs $10.00 per 1M blended).
| Metric | Claude Opus 4.5 (thinking) | Grok 4 |
|---|---|---|
| BenchLeader Index | 59.4 | 59.8 |
| Agents & tools score | 69.7 | 53.4 |
| Coding score | 60.5 | 61.2 |
| Composite score | 60.0 | – |
| Instruction following score | 53.5 | 67.7 |
| Knowledge score | 60.3 | 56.0 |
| Long context score | 62.5 | 77.7 |
| Maths score | 64.0 | 58.0 |
| Multimodal score | 57.0 | 54.5 |
| Reasoning score | 58.6 | 58.3 |
| Human preference score | – | 59.8 |
| Blended price $/M | $10.00 | $1.56 |
| Output speed | 44 tok/s | – |
| Time to first answer | 13.7 s | – |
| Context window | 200k | 256k |
| GPQA Diamond | – | 87.0% |
| OTIS Mock AIME | – | 84.0% |
| Terminal-Bench | – | 27.2% |
| SimpleBench | – | 60.5% |
| Fiction.LiveBench 120k | – | 96.9% |
| Cybench | – | 43.0% |
| WeirdML | – | 45.7% |
| APEX-Agents | – | 15.2% |
| Epoch Capabilities Index | – | 146.4 |
| LMArena Text | – | 1411 |
| LMArena Hard Prompts | – | 1420 |
| LMArena Coding | – | 1435 |
| LMArena Vision | – | 1210 |
| AA Intelligence Index | 29.1 | – |
| IFBench | 58.0% | – |
| AA-LCR | 77.3% | – |
| MMMU-Pro | 74.0% | – |
| AA-Omniscience | 14 | – |
| Terminal-Bench Hard | 47.0% | – |
| GPQA Diamond (AA) | 86.6% | – |
| Humanity's Last Exam (AA) | 30.1% | – |
| τ²-Bench Telecom (AA) | 89.5% | – |
| AIME (Vals) | 95.4% | 90.6% |
| LiveCodeBench | 83.7% | 83.3% |
| MMLU-Pro | 87.3% | 85.3% |
| LegalBench | 84.6% | 83.2% |
| CorpFin | 65.1% | 66.0% |
| TaxEval | 74.9% | 65.1% |
| MedQA | 95.9% | 92.5% |
| MGSM | 95.2% | 90.9% |
| SWE-bench (Vals) | 76.4% | 57.8% |
| GPQA Diamond (Vals) | 85.9% | 88.1% |
| IMO 2025 | – | 21.4% |
| MathArena Apex | – | 2.1% |
| MultiChallenge | 59.0% | – |
| PRBench Finance | 46.2% | – |
| PRBench Legal | 44.2% | – |
| VISTA | 46.4% | – |
| MultiNRC | 48.6% | – |
| TutorBench | 51.2% | – |
| Kagi LLM Benchmark | 80.2% | 73.6% |
| IFEval (HELM) | – | 94.9% |
| Omni-MATH (HELM) | – | 60.3% |
| WildBench (HELM) | – | 79.7% |
| MMLU-Pro (HELM) | – | 85.1% |
| GPQA Diamond (HELM) | – | 72.6% |
| HELM Capabilities mean | – | 78.5% |
| Aider Polyglot | – | 79.6% |
| ARC-AGI-1 | 80.0% | 79.6% |
| ARC-AGI-2 | 37.6% | 29.4% |
| BFCL Overall | – | 63.0% |
Data as of 2026-09-13. Best configuration of each model; every score links to its source on the model pages.
Claude Opus 4.5 vs Grok 4: questions
- Is Claude Opus 4.5 better than Grok 4?
- Claude Opus 4.5 (thinking) and Grok 4 are level on quality (59.4 vs 59.8). The BenchLeader Index combines every independent quality benchmark; Grok 4 is ahead overall as of 2026-09-13, but check the category scores for your use.
- Is Claude Opus 4.5 better than Grok 4 for coding?
- Grok 4 scores higher in coding (61 vs 61 on the category index, where 50 is average).
- Is Claude Opus 4.5 better than Grok 4 for agentic tasks?
- Claude Opus 4.5 scores higher in agentic tasks (70 vs 53 on the category index, where 50 is average).
- Which is cheaper, Claude Opus 4.5 or Grok 4?
- Grok 4 is cheaper: $1.56 against $10.00 per million tokens, blended at three input tokens per output token.
- Which has the larger context window?
- Grok 4 accepts more context: 256k against 200k tokens.