OpenAI: GPT-5.6 Sol Pro

OpenAI's GPT-5.6 Sol Pro, released on July 9, 2026, is designed for higher-quality responses on complex tasks, leveraging a substantial 1,050,000 context length. This model demonstrates competitive response times, ranking in the 49th percentile across benchmarks, indicating it performs among the faster models available. However, its pricing is positioned at a premium level, ranking in the 2nd percentile, making it one of the more expensive options. A standout feature is its exceptional reliability, achieving a perfect 100% success rate across all 8 benchmarks, ensuring consistent and usable responses. The model exhibits strong performance across various categories. It achieves perfect accuracy in General Knowledge and Ethics, with the former also being noted as the most accurate at its price point and speed. Instruction Following and Reasoning are also significant strengths, scoring 92.0% (96th percentile) and 98.0% (83rd percentile) respectively. Coding and Mathematics benchmarks show solid results at 95.0% and 94.0% accuracy. While its Hallucinations accuracy is 96.0% (49th percentile), indicating a reasonable ability to acknowledge uncertainty, it's not among the top performers in this specific area. Email Classification is also competitive at 98.0% accuracy. Overall, GPT-5.6 Sol Pro excels in accuracy for complex tasks and knowledge-based queries, making its premium cost justifiable for applications demanding high precision and reliability.