Convert between different pressure units including pascal, bar, atmosphere, psi, torr and more with precise calculations and instant results.
Standard atmospheric pressure at sea level is 101,325 Pascals (Pa), 1 atmosphere (atm), or about 14.7 pounds per square inch (psi). This pressure is caused by the weight of the air above us.
Water pressure increases by approximately 1 atmosphere (101,325 Pa) for every 10 meters of depth. This is why deep-sea creatures have evolved to withstand extreme pressures.
The unit "Torr" is named after Evangelista Torricelli, who invented the mercury barometer in 1643. One Torr is equivalent to the pressure exerted by a 1 mm column of mercury at 0°C and standard gravity.
The vacuum of space isn't completely empty. Interstellar space has an extremely low pressure of about 10^-19 Pa. Even the best laboratory vacuums on Earth can only reach about 10^-12 Pa.