Pressure Converter
Convert psi, bar, atm, pascal, kPa, and mmHg.
Unit
Pressure Converter
Generated on April 24, 2026
?What is the Pressure Converter?
A pressure converter translates between the many units used for pressure: pascals (SI base), kilopascals, bar (near-atmospheric), atmospheres (atm), pounds per square inch (psi, imperial), and millimeters of mercury (mmHg, used in medicine). Pressure is force per unit area, and each unit has its typical application. Tire pressure is almost always in psi or bar; weather reports use hPa or mbar; scuba divers think in atmospheres; and blood pressure is stated in mmHg. This tool cleanly moves between all six.
The Formula
The pascal (Pa) is the SI unit: 1 newton per square meter. That is a tiny amount of pressure, so practical values are expressed in kPa, bar, or atm. Standard atmospheric pressure at sea level is 101,325 Pa — which explains why 1 atm and 1 bar are so close (bar was defined as a convenient round approximation to atmospheric pressure). PSI (pound-force per square inch) is the imperial legacy unit, still standard in tires and pneumatic systems.
Practical Examples
Car tire pressure of 32 psi equals 2.21 bar or 221 kPa — the range typically recommended for passenger cars.
Sea-level atmospheric pressure is 101.325 kPa, or 1 atmosphere, or about 1.013 bar — the default comparison baseline.
Blood pressure of 120 mmHg systolic equals 16 kPa — useful when medical equipment shows metric units.
Engine oil pressure at normal operating speed is typically 40–70 psi, or 275–480 kPa.
Scuba diving at 10 meters depth adds 1 atm of water pressure, giving 2 atm total — which is why divers must equalize regularly.
A typical weather 'high pressure' system reads 1,025 hPa (102.5 kPa), while a strong storm system might drop below 980 hPa (98 kPa).