GPT-5.5 Pro vs GPT-4o
Side-by-side comparison. Updated 2026-06-04.
Verdict
GPT-5.5 Pro wins on higher overall score (9.5 vs 7.5, +2.0).
- Larger context window (1050k vs 128k)
At a Glance
| Attribute | GPT-5.5 Pro | GPT-4o |
|---|---|---|
| Provider | OpenAI | OpenAI |
| Tags | Reasoning | general |
| Context | 1,050,000 tokens | 128,000 tokens |
| Input price | $30.00/1M | $2.50/1M |
| Output price | $10.00/1M | $10.00/1M |
| Input modalities | Text | Text |
| Output modalities | Text | Text |
GPT-5.5 Pro Strengths
GPT-4o Strengths
- Strong general capability
- Widely available
- Low pricing
- Huge ecosystem