OpenAI GPT-5.5 is a frontier model for the most complex professional work. It raises the baseline for complex production workflows. It is a strong fit for coding use cases, tool-heavy agents, grounded assistants, long-context retrieval, product-spec-to-plan workflows, and customer-facing workflows where execution quality and response polish are critical.Documentation Index
Fetch the complete documentation index at: https://developer.box.com/llms.txt
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Model details
| Item | Value | Description |
|---|---|---|
| Model name | GPT-5.5 | The name of the model. |
| Model category | Premium | The category of the model: Standard or Premium. |
| API model name | openai__gpt_5_5 | The name of the model that is used in the . You must provide this exact name for the API to work. |
| Compliance | N/A | Government compliance frameworks and authorizations applicable to this model. |
| Hosting layer | OpenAI | The trusted organization that securely hosts the LLM. |
| Model provider | OpenAI | The organization that provides this model. |
| Release date | April 23, 2026 | The release date for the model. |
| Knowledge cutoff date | December 01, 2025 | The date after which the model does not get any information updates. |
| Input context window | 1m tokens | The number of tokens supported by the input context window. |
| Maximum output tokens | 128k tokens | The number of tokens that can be generated by the model in a single request. |
| Empirical throughput | Not specified | The number of tokens the model can generate per second. |
| Open source | No | Specifies if the model’s code is available for public use. |