Convert pressure between any units instantly — pascal, kilopascal, bar, atmosphere, PSI, mmHg, torr, and more. Works for weather, tyre pressure, blood pressure, and industrial use.
Pressure is force per unit area. P = F/A. The SI unit is the pascal (Pa) = 1 N/m². Common units include bar, atmosphere (atm), PSI (pounds per square inch), and mmHg.
Standard atmospheric pressure at sea level is 101,325 Pa = 1 atm = 1.01325 bar = 14.696 PSI = 760 mmHg. This is the reference point for many pressure measurements.
Most passenger car tyres require 30-35 PSI (206-241 kPa). Check the sticker inside your driver door jamb or the owner manual for the correct specification — not the number on the tyre sidewall.
Normal blood pressure is around 120/80 mmHg. In pascals: 120 mmHg = 15,998 Pa = 15.99 kPa. Blood pressure is always measured in mmHg in clinical practice worldwide.
Absolute pressure is measured from zero (perfect vacuum). Gauge pressure is measured relative to atmospheric pressure. Tyre pressure gauges show gauge pressure — a reading of 30 PSI means 30 PSI above atmospheric.
1 pascal = 1 newton per square metre (N/m²). It is a very small unit — atmospheric pressure is about 101,325 Pa. Weather forecasts often use hectopascals (hPa, 1 hPa = 100 Pa), where standard pressure is 1013.25 hPa.
1 atm = 101,325 Pa. 1 bar = 100,000 Pa. They are very close but not equal: 1 atm ≈ 1.01325 bar. The bar is used in meteorology and engineering; the atmosphere is used in chemistry and diving.