Upstage: Solar Pro 4

Upstage's Solar Pro 4, created on August 10, 2026, is a large language model designed for agentic workflows, office productivity, document-intensive tasks, and coding. It performs among the fastest models, typically ranking in the top tier for speed (77th percentile across 8 benchmarks), and consistently offers among the most competitive pricing (90th percentile). The model demonstrates exceptional reliability, achieving a 100% success rate across all benchmarks, indicating minimal technical failures. Solar Pro 4 exhibits strong performance in several key areas. It excels in General Knowledge, achieving 99.5% accuracy and being highlighted as the most accurate model at its price point. Its Mathematics capabilities are also impressive, with 95.0% accuracy (87th percentile). The model shows solid performance in Coding (90.0% accuracy) and Ethics (99.0% accuracy). While its Hallucinations accuracy is 94.0%, it falls in the 47th percentile, suggesting room for improvement in acknowledging uncertainty. A notable weakness is its Instruction Following, where it achieved only 45.0% accuracy (32nd percentile), indicating challenges with complex, multi-layered instructions.