GPT-5.5
OpenAI's latest flagship model. Significant improvements in reasoning, coding, and general capability over GPT-5. Available via API and ChatGPT.
Specifications
| Lab | OpenAI |
|---|---|
| Context window | 1.1M tokens |
| Input price | $5.00/1M |
| Output price | $30.00/1M |
| Release | Apr 2026 |
Strengths
- Strong general knowledge
- Deep reasoning chain-of-thought
- Reliable structured output
- Broad tool-use capability
- Excellent multilingual support
Weaknesses
- Creative writing less nuanced than Claude
- High cost for API usage
Best for
- General purpose tasks
- Tool calling & agents
- Data analysis
- Structured output pipelines
In Depth: GPT-5.5
Summary
GPT-5.5 is an AI model from OpenAI.
Released in Apr 2026. It currently appears in the Overall category on LMRank. It takes text input and produces text output, with a context window of 1.1M tokens. Input pricing is $5.00 per 1M tokens and output is $30.00 per 1M tokens on OpenRouter.