what is 1 atm

The standard atmosphere (symbol: atm) is a unit of pressure that represents the average atmospheric pressure at sea level on Earth. It is a fundamental reference point used in science, particularly for describing the properties of gases. One atmosphere is precisely defined as 101,325 Pascals (Pa), which is the SI unit of pressure. This is also equivalent to 101.325 kilopascals (kPa), approximately 1.013 bar, or 760 millimetres of mercury (mmHg).