OpenAI: GPT-5.5 Pro vs OpenAI: o3 Deep Research
Side-by-side comparison. Updated 2026-06-07.
Verdict
OpenAI: GPT-5.5 Pro wins on higher overall score (9.5 vs 9.0, +0.5).
- Larger context window (1050k vs 200k)
At a Glance
| Attribute | OpenAI: GPT-5.5 Pro | OpenAI: o3 Deep Research |
|---|---|---|
| Provider | OpenAI | OpenAI |
| Tags | Intelligent Reasoning Coding Agentic Long Context | Reasoning Agentic Intelligent |
| Context | 1,050,000 tokens | 200,000 tokens |
| Input price | $30.00/1M | $10.00/1M |
| Output price | $40.00/1M | $40.00/1M |
| Input modalities | File, Image, Text | Image, Text, File |
| Output modalities | Text | Text |
OpenAI: GPT-5.5 Pro Strengths
- Unmatched deep reasoning for complex high-stakes workloads
- 1M+ token context window with image input support
- Excels at long-horizon agents and multi-step coding
- Precise execution across agentic workflows
OpenAI: o3 Deep Research Strengths
- Best-in-class multi-step research and synthesis
- Thorough source evaluation and cross-referencing
- Handles ambiguous open-ended questions well
- Produces cited, well-structured research reports