GPT-5.3 vs GPT-5.5 Pro
Side-by-side comparison. Updated 2026-07-11.
Summary
Compare GPT-5.3 and GPT-5.5 Pro across pricing, context window, modalities, strengths, weaknesses, and best-fit workloads.
Use the details below to weigh cost, context, modalities, and workload fit.
At a Glance
| Attribute | GPT-5.3 | GPT-5.5 Pro |
|---|---|---|
| Provider | OpenAI | OpenAI |
| Tags | Intelligent Reasoning Coding Multimodal | Agentic Coding Intelligent Long Context Reasoning |
| Context | 400,000 tokens | 1,050,000 tokens |
| Input price | $11.00/1M | $30.00/1M |
| Output price | $44.00/1M | $180.00/1M |
| Input modalities | Text, Image, File | Image, Text |
| Output modalities | Text | Text |
GPT-5.3 Strengths
- Improved agentic coding
- Reliable multi-step tool use
- 400K context window
- File and image input
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