Deepseek v4 Pro vs GPT-5.5 Pro
Deepseek v4 Pro 
GPT-5.5 Pro Verdict
- GPT-5.5 Pro (xhigh) leads on quality: 67.1 vs 60.8.
- Deepseek v4 Pro (high) is stronger in coding, human preference.
- GPT-5.5 Pro (xhigh) is stronger in maths, reasoning.
| Metric | Deepseek v4 Pro (high) | GPT-5.5 Pro (xhigh) |
|---|---|---|
| BenchLeader Index | 60.8 | 67.1 |
| Coding score | 59.3 | – |
| Human preference score | 66.1 | – |
| Maths score | 66.1 | 74.5 |
| Reasoning score | 65.9 | 80.1 |
| Blended price $/M | – | $67.50 |
| Output speed | – | 4 tok/s |
| Time to first answer | – | 3.5 s |
| Context window | – | 1.1M |
| GPQA Diamond | 90.9% | – |
| FrontierMath Tiers 1–3 | – | 87.7% |
| FrontierMath Tier 4 | – | 78.0% |
| OTIS Mock AIME | 95.6% | – |
| SciCode | 46.4% | – |
| WeirdML | 46.5% | – |
| LMArena Text | 1463 | – |
| LMArena Hard Prompts | 1482 | – |
| LMArena Coding | 1503 | – |
| LMArena WebDev | 1581 | – |
| ARC-AGI-1 | – | 95.0% |
| ARC-AGI-2 | – | 84.2% |
| CritPt | – | 30.6% |
| LMArena Maths | 1469 | – |
| LMArena Creative Writing | 1442 | – |
| LMArena Instruction Following | 1457 | – |
| LMArena Multi-turn | 1469 | – |
| LMArena Longer Queries | 1474 | – |
| Chess Puzzles | 13.0% | – |
| CL-bench Life | 13.5% | – |
| Surface Evolver Bench | 40.0% | – |
| LMCA | – | 53.9% |
| DTBench | – | 96.0% |
| ALE-Bench | 1006.1 | – |
Data as of 2026-09-19. Best configuration of each model; every score links to its source on the model pages.
Deepseek v4 Pro vs GPT-5.5 Pro: questions
- Is Deepseek v4 Pro better than GPT-5.5 Pro?
- GPT-5.5 Pro (xhigh) leads on quality: 67.1 vs 60.8. The BenchLeader Index combines every independent quality benchmark; GPT-5.5 Pro (xhigh) is ahead overall as of 2026-09-19, but check the category scores for your use.