# Millimeter of water conversions

The millimeter of water conversion selector selects the pressure/stress measurement unit to convert to starting from millimeters of water (mmH2O). To make a conversion starting from a unit of pressure other than millimeter of water, simply click on the "Reset" button.

## About millimeter of water

The **millimeter of water** is a unit of pressure equal to 9.80638 pascals (1 mmH_{2}O = 9.80638 Pa), the SI derived unit of pressure.

The millimeter of water (mmH_{2}O) is also equal to 0.0980638 hectopascals (hPa), or 0.00980638 kilopascals (kPa), or about 0.000096781 atmospheres (atm), or 0.0980638 millibars (mbar), or 0.073554 millimeters of mercury at 0 °C (mmHg), or 0.03937 inches of water at 4 °C (inH_{2}O), or 0.0014223 pounds per square inch (psi), or 0.2048105 pounds per square foot (psf) or 0.073554 torr (Torr).

The millimeters of water is the pressure applied by a column of water one millimeter high at 4 °C in a gravitational field.

The millimeter of water is used to measure lung pressures.

Symbol: mmH_{2}O

Plural: millimeters of water

Also called: millimetre of water (plural: millimetres of water, Int. spelling)