Pressure Converter

1 bar equals 14.5038 psi. A car tire inflated to 2.3 bar is about 33.4 psi - just multiply bar by 14.5038 to convert. Bar is the standard on European pressure gauges; psi is the default in the US. Both express absolute or gauge pressure, so the math translates directly.

Standard atmospheric pressure at sea level is 1 atm, which equals 101,325 Pa (101.325 kPa), 1.01325 bar, 14.6959 psi, and 760 mmHg. Weather reports sometimes call this 1013.25 hPa (hectopascals), which is the same value expressed in different units.

Blood pressure has been reported in millimeters of mercury since mercury manometers were the standard clinical tool in the 19th century. The unit stuck because regulators and clinicians built reference ranges around it. A reading of 120/80 mmHg converts to roughly 16.0/10.7 kPa, though medical guidelines still use mmHg worldwide.

In this calculator, torr and mmHg are treated as identical: both use 133.322 Pa per unit, which is 1/760 of a standard atmosphere. The two units differ by less than 0.000015% in the strict definition, making them interchangeable for every practical purpose.

Inches of mercury (inHg) is used in US aviation for altimeter settings and in US weather broadcasts for barometric pressure. 1 inHg equals 3,386.39 Pa, or about 0.0334 atm. Standard sea-level pressure is 29.9213 inHg, which is the value you see as the default altimeter setting in calm weather.