OpenAI: GPT-5.5

GPT-5.5 is a paid model from OpenAI that accepts text, images, and files as input. It supports tool use and reasoning, and its context window reaches 1,050,000 tokens, with up to 128,000 tokens per completion. Structured output support is unconfirmed based on available data. At $5.00 per million input tokens and $30.00 per million output tokens, this is a premium-tier option. Its blended benchmark score of 93.7 draws from four benchmarks, including a perfect 100 on coding and 90.5 on the AI Index overall, though agentic performance (74.0) and emotional reasoning (82.4) trail the headline figure. The output cost in particular will matter for high-volume use cases, so teams doing heavy generation at scale should model that expense carefully. Those prioritizing strong coding performance and broad context handling, and who can absorb the pricing, have the most reason to shortlist it here.