
GPT-5.5 via OpenAI
Specifications
Context Window
1,050,000 tokens
Release Date
2026-04-23
Capabilities
AttachmentsReasoningTool callingStructured outputImage inputPdf input
Availability
Proprietary API
Model Overview
OpenAI is the creator of the GPT series and o-series reasoning models. Known for ChatGPT and the GPT-4 family, OpenAI offers some of the most widely used language models for general-purpose AI tasks, code generation, and multimodal understanding.
GPT-5.5 is a gpt-family model by OpenAI with a 1.1M token context window and up to 128k output tokens. It is priced at $5.00/1M input tokens and $30.00/1M output tokens.
Key capabilities include: attachments, reasoning, tool calling, structured output, image input, pdf input. It supports advanced reasoning for complex multi-step tasks. It can call external tools and functions for agentic workflows.






