# Pascal

*This article is about the unit of pressure; for other uses see Pascal (disambiguation)*

**pascal**(symbol

**Pa**) is the SI unit of pressure. It is equivalent to one newton per square metre. The unit is named after Blaise Pascal, a French mathematician, physicist and philosopher.

Since 1 Pa is a small pressure, the unit **hectopascal** (symbol **hPa**) is more widely used, especially in meteorology. The unit **kilopascal** (symbol **kPa**) is also in common use.

- 1 hectopascal = 100 pascal = 1 millibar
- 1 kilopascal = 1000 pascal = 10 hectopascal

The same unit is used to measure stress, Young's modulus and tensile strength.

Table of contents |

2 Comparison to other units of pressure 3 External links |

## Examples of various values (approximately)

(See SI prefix for guide to units.)

0.5 Pa | Atmospheric pressure on Pluto (1988 figure; very roughly) |

9.81 Pa | The pressure caused by a depth of 1 mm of water¹ |

1 kPa | Atmospheric pressure on Mars |

10 kPa | The pressure caused by a depth of 1 m of water, or the drop in air pressure when going from sea level to 1000 m elevation¹ |

101.3 kPa | Atmospheric pressure at sea level¹ |

10 MPa | Pressure washer forces out water at this pressure |

100 MPa | Pressure at bottom of Mariana Trench, about 10 km under ocean¹ |

10 GPa | Diamond forms |

100 GPa | Theoretical tensile strength of carbon nanotubes (CNTs) |

## Comparison to other units of pressure

1 bar | 100,000 Pa |

1 millibar | 100 Pa |

1 atmosphere | 101,325 Pa |

1 mmHg (or torr)
| 133 Pa |

1 inch Hg | 3,386 Pa |

## External links