Online calculator to accurately transform pressure units like Pascal, Bar, ATM, and PSI.
Pressure measures force applied per unit of area, and its scientific history begins with one of the most elegant discoveries of the 17th century: Blaise Pascal proved, in 1648, that air itself has measurable weight, sending his brother-in-law to a mountaintop with a barometer to prove that atmospheric pressure decreases with altitude. Multiple pressure unit systems exist in simultaneous use today, each dominant in a different context: the pascal (the official SI unit) in physics and engineering, PSI (pounds per square inch) in tires and hydraulic systems in the United States, the bar in European industrial equipment, and the hectopascal (equivalent to the old millibar) in meteorology, used to describe atmospheric pressure in weather forecasts and hurricane maps. This converter calculates precisely between all these units, critical for mechanics calibrating tire pressure with specifications from manufacturers in different countries, divers calculating pressure at depth (where every 10 metres of water adds approximately 1 atmosphere of pressure), HVAC technicians working with refrigeration systems, and industrial process engineers where incorrect pressure can mean anything from inefficiency to a real safety risk in pressurized equipment.
Pound per Square Inch, common for measuring tire pressure.
1 Bar is equivalent to approximately 0.9869 ATM.
The Pascal (Pa) is the base unit of the International System.
1 Atmosphere (ATM) equals 101,325 Pascals.
Yes, the conversion from PSI to Bar or ATM is exact for this purpose.
1 bar ≈ 14.5038 psi.
Both are used. 30 psi ≈ 2.07 bar. Use the converter for the exact value.
1 atmosphere (atm) = 101,325 pascals (Pa).