OpenAI: GPT-5.5 Pro
GPT-5.5 Pro is OpenAI’s high-capability model optimized for deep reasoning and accuracy on complex, high-stakes workloads. It features a 1M+ token context window (922K input, 128K output) with support for...
Everything else
| Max output | 128K |
|---|---|
| Input / 1M | $30 |
| Output / 1M | $180 |
| Cache read / 1M | — |
| Cache write / 1M | — |
| 1M in + 1M out | $210 |
| Takes | file, image, text |
| Returns | text |
| Tools | yes |
| Reasoning | always on · xhigh, high, medium |
| Open weights | no |
| Released | 2026-04-24 |
| Knowledge cutoff | 2025-12-01 |
| Retires | — |
| Catalog id | openai/gpt-5.5-pro |
Benchmarks
| source | epoch |
|---|---|
| eci | 160.86 |
| confidence | Likely |
| accessibility | API access |
Benchmark scores by Epoch AI, CC BY 4.0.
Using it
In 00, this model is picked per agent — and per tier, so the model that answers your customers need not be the one that writes your code. Get 00.