GPT-5 Pro vs Grok 4.5
GPT-5 Pro 
Grok 4.5 Verdict
- Grok 4.5 leads on quality: 63.5 vs 60.8.
- GPT-5 Pro is stronger in multimodal.
- Grok 4.5 is stronger in knowledge, reasoning, agents & tools, coding, composite, human preference, long context.
- Grok 4.5 is 14× cheaper ($3.00 vs $41.25 per 1M blended).
| Metric | GPT-5 Pro | Grok 4.5 |
|---|---|---|
| BenchLeader Index | 60.8 | 63.5 |
| Knowledge score | 68.0 | 76.2 |
| Multimodal score | 67.4 | 64.9 |
| Reasoning score | 57.6 | 69.2 |
| Agents & tools score | – | 58.6 |
| Coding score | – | 59.8 |
| Composite score | – | 66.2 |
| Human preference score | – | 67.2 |
| Long context score | – | 66.2 |
| Blended price $/M | $41.25 | $3.00 |
| Output speed | – | 52 tok/s |
| Time to first answer | – | 13.6 s |
| Context window | 400k | 500k |
| Humanity's Last Exam | 31.6% | – |
| SimpleBench | 61.6% | 70.0% |
| WeirdML | – | 46.4% |
| APEX-Agents | – | 34.2% |
| FrontierCode | – | 42.4% |
| Epoch Capabilities Index | 150.3 | 153.9 |
| LMArena Text | – | 1471 |
| LMArena Hard Prompts | – | 1495 |
| LMArena Coding | – | 1523 |
| LMArena WebDev | – | 1556 |
| LMArena Vision | – | 1291 |
| LMArena Agent | – | 3.9 |
| LiveBench | – | 75.8% |
| LiveBench Reasoning | – | 87.2% |
| LiveBench Coding | – | 68.6% |
| LiveBench Agentic Coding | – | 56.5% |
| LiveBench Mathematics | – | 90.8% |
| LiveBench Data Analysis | – | 73.0% |
| LiveBench Language | – | 82.8% |
| AA Intelligence Index | – | 39.1 |
| AA-LCR | – | 79.3% |
| MMMU-Pro | – | 80.4% |
| AA-Omniscience | – | 25.3 |
| GPQA Diamond (AA) | – | 93.1% |
| Humanity's Last Exam (AA) | – | 42.7% |
| SciCode (AA) | – | 55.0% |
| PRBench Finance | 51.1% | – |
| PRBench Legal | 49.9% | – |
| VISTA | 52.4% | – |
| MultiNRC | 65.2% | – |
| Kagi LLM Benchmark | 76.8% | 83.5% |
| ARC-AGI-1 | 70.2% | – |
| ARC-AGI-2 | 18.3% | – |
Data as of 2026-09-10. Best configuration of each model; every score links to its source on the model pages.
GPT-5 Pro vs Grok 4.5: questions
- Is GPT-5 Pro better than Grok 4.5?
- Grok 4.5 leads on quality: 63.5 vs 60.8. The BenchLeader Index combines every independent quality benchmark; Grok 4.5 is ahead overall as of 2026-09-10, but check the category scores for your use.
- Which is cheaper, GPT-5 Pro or Grok 4.5?
- Grok 4.5 is cheaper: $3.00 against $41.25 per million tokens, blended at three input tokens per output token.
- Which has the larger context window?
- Grok 4.5 accepts more context: 500k against 400k tokens.