Therefore: At IUPAC standard temperature and pressure (0 °C and 100 kPa), dry air has a density of 1.2754 kg/m³. At 20 °C and 101.325 kPa, dry air has a density of 1.2041 kg/m³. At 70 °F and 14.696 psi, dry air has a density of 0.074887 lb/ft³.