How it works
Convert pressures used for tires, weather, blood pressure, HVAC and engineering. The SI unit is the pascal (one newton per square meter); kilopascals and bars are common in Europe, and psi is standard in the US.
The standard atmosphere is defined as exactly 101,325 Pa, which is about 14.6959 psi, 1.01325 bar, 760 mmHg or 29.92 inHg. One psi is exactly 0.45359237 kg × 9.80665 m/s² of force on a square inch, about 6,894.76 Pa.
Formula
Result = value × (Pa per from-unit) ÷ (Pa per to-unit). 1 atm = 101,325 Pa; 1 psi ≈ 6,894.757 Pa.
Questions people ask
How many psi is 1 bar?
About 14.5038 psi. One psi is about 0.0689476 bar.
Is gauge pressure different from absolute pressure?
Yes. Gauge pressure (psig) is measured relative to the surrounding air, so a tire at 32 psig is about 46.7 psi absolute at sea level. The conversion factors are the same for both.
What is the difference between mmHg and torr?
They differ by less than 0.000015%. A torr is exactly 1/760 of an atmosphere, while a millimeter of mercury is defined from the density of mercury and standard gravity.
What is normal air pressure in inches of mercury?
Standard sea-level pressure is 29.92 inHg (1013.25 hPa). Weather reports use these units for barometric pressure.