"Pascals" redirects here. For other uses, see pascal (disambiguation).
A pressure gauge reading in psi (red scale) and kPa (black scale)
|Unit system||SI unit|
|Unit of||Pressure or stress|
|Named after||Blaise Pascal|
|1 Pa in ...||... is equal to ...|
| SI base units:|| kg⋅m−1⋅s−2|
| US customary units:|| 1.450×10−4 psi|
| atmosphere:|| 9.869×10−6 atm|
| bar:|| 10−5 bar|
The pascal (symbol: Pa) is the SI derived unit of pressure used to quantify internal pressure, stress, Young's modulus and ultimate tensile strength. The unit, named after Blaise Pascal, is defined as one newton per square metre. The unit of measurement called standard atmosphere (atm) is defined as 101325 Pa.
Common multiple units of the pascal are the hectopascal (1 hPa = 100 Pa) which is equal to one millibar, and the kilopascal (1 kPa = 1000 Pa) which is equal to one centibar. Meteorological forecasts typically report atmospheric pressure in hectopascals per the recommendation of the World Meteorological Organization. Forecasts in the United States typically use millibars, in Canada these reports are given in kilopascals.