GPT-5.5 Pro
GPT-5.5 Pro
📌 Model Overview
Highest-accuracy GPT-5.5 tier for slower, precision-heavy reasoning and coding
GPT-5.5 Pro is a Api Only model developed by OpenAI, released on 2026-04-23. It is designed primarily for Chat Reasoning workloads. Featuring a 1.1M tokens context window and Undisclosed parameter count, it offers robust performance for enterprise integration, developers, and researchers.
✨ Key Features & Capabilities
| Feature | Description |
|---|---|
| Context Window | 1.1M tokens capacity for extended prompts and multi-turn workflows |
| Primary Task | Optimized for Chat Reasoning |
| Deployment | api-only |
| Modality | text, image, pdf |
| Max Output | Max Output: 128K tokens |
| Native reasoning capability | Native reasoning capability |
| Tool / function calling support | Tool / function calling support |
⚙️ Technical Specifications
| Specification | Details |
|---|---|
| Developer / Lab | OpenAI |
| Release Date | 2026-04-23 |
| Model Type | Api Only |
| Parameters | Undisclosed |
| Context Window | 1.1M tokens |
| License | Proprietary |
| Model Family | gpt-pro |
📊 Benchmarks & Performance
| Benchmark | Score | Source |
|---|---|---|
| BrowseComp | 90.1 (accuracy) | Independent Eval |
| Humanity's Last Exam | 43.1 (accuracy) | Independent Eval |
| Humanity's Last Exam | 57.2 (accuracy) | Independent Eval |
| FrontierMath | 52.4 (accuracy) | Independent Eval |
| FrontierMath | 39.6 (accuracy) | Independent Eval |
| GDPval | 82.3 (wins or ties) | Independent Eval |
| GeneBench | 33.2 (accuracy) | Independent Eval |
💰 Pricing
| Tier / Unit | Rate (USD) |
|---|---|
| 1M input tokens | $30 |
| 1M output tokens | $180 |
📜 License & Usage
This model is governed by the Proprietary license. Please check official developer guidelines before commercial deployment.
Key Features
Max Output: 128K tokens
Native reasoning capability
Tool / function calling support
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Verified Sources
Tags
Model Specs
Parameters
Undisclosed
Context Window
1.1M tokens
License
Proprietary
Deployment
Pricing
- 1M input tokens$30
- 1M output tokens$180
as of 2026-07-26
Lineage
Curator Notes
Skeleton entry imported from models.dev backfill (2026-07-26). Needs manual enrichment and primary-source verification.
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