Numerical commonsense refers to the intuitive, everyday understanding of numbers, quantities, and basic numerical relationships that humans routinely use to interpret the physical world. In artificial intelligence and natural language processing, it denotes the capability of a system to recognize and reason over implicit numerical properties and quantitative facts associated with real-world entities, such as the standard count of limbs on an animal, typical ranges of physical dimensions, or reasonable durations of everyday events. This form of commonsense bridges quantitative logic and language comprehension, allowing models to evaluate whether numerical statements are plausible, estimate approximate magnitudes, and perform basic arithmetic reasoning within everyday contexts without requiring explicit formal calculation.