Key takeaways

• GPT-5.5 is OpenAI's frontier model for complex professional workloads, building on GPT-5.4 with stronger reasoning and higher reliability, designed for coding, research, data analysis, and multi-step workflows. It processes text, image, and file inputs to text outputs, with a context length of 1,050,000 tokens.
• The model utilizes a Mixture of Experts (MoE) architecture, suggesting an efficient and specialized processing approach. It is proprietary, meaning its weights are not publicly accessible.
• GPT-5.5 excels in wide-ranging mathematical domains and straightforward terminal commands (file operations, common developer tasks, basic web scraping). However, it struggles with complex system configurations, advanced kernel compilation, intricate blockchain services, and specific output formatting requirements.
• On the 'MATH-500' dataset, GPT-5.5 achieved a 97% accuracy, demonstrating strong mathematical problem-solving capabilities, including multi-step reasoning, symbolic manipulation, and precise calculations. Despite this, some errors were due to strict formatting rather than mathematical inaccuracy.
• On the 'Terminal-Bench (Terminus-2)' dataset, the model achieved a 55% accuracy and a 56.25% pass rate (45/80 tasks). While proficient in common developer tasks and file system operations, it showed significant weaknesses in tasks requiring complex system administration, networking, security configurations, and intricate algorithmic implementations such as Nginx setup or QEMU interactions.

Technical specifications

Context length

1M tokens

Max output

—

Architecture

MoE

Modalities

text+image+file->text

Parameters

—

Open weights

No

Licence

Proprietary

Regions

USA

Vendor

OpenAI

Provider model key

openai/gpt-5.5-20260423