How many inch mercury in 1 mmH2O? The answer is 0.0028959017998228. We assume you are converting between inch mercury [0 °C] and millimeter of water [4 °C]. You can view more details on each measurement unit: inch mercury or mmH2O The SI derived unit for pressure is the pascal. 1 pascal is equal to 0.00029529980164712 inch mercury, or 0.10197162129779 mmH2O. Note that rounding errors may occur, so always check the results. Use this page to learn how to convert between inches mercury and millimeters of water. Type in your own numbers in the form to convert the units!
1 inch mercury to mmH2O = 345.31558 mmH2O
2 inch mercury to mmH2O = 690.63115 mmH2O
3 inch mercury to mmH2O = 1035.94673 mmH2O
4 inch mercury to mmH2O = 1381.26231 mmH2O
5 inch mercury to mmH2O = 1726.57788 mmH2O
6 inch mercury to mmH2O = 2071.89346 mmH2O
7 inch mercury to mmH2O = 2417.20904 mmH2O
8 inch mercury to mmH2O = 2762.52461 mmH2O
9 inch mercury to mmH2O = 3107.84019 mmH2O
10 inch mercury to mmH2O = 3453.15577 mmH2O
You can do the reverse unit conversion from mmH2O to inch mercury, or enter any two units below:
Inches of mercury or inHg is a non-SI unit for pressure. It is still widely used for barometric pressure in weather reports and aviation in the United States, but is considered somewhat outdated elsewhere.
It is defined as the pressure exerted by a column of mercury of 1 inch in height at 32 °F (0 °C) at the standard acceleration of gravity.
1 inHg = 3,386.389 pascals at 0 °C.
Aircraft operating at higher altitudes (above 18,000 feet) set their barometric altimeters to a standard pressure of 29.92 inHg or 1,013.2 hPa (1 hPa = 1 mbar) regardless of the actual sea level pressure, with inches of mercury used in the U.S. and Canada. The resulting altimeter readings are known as flight levels.
Piston engine aircraft with constant-speed propellers also use inHg to measure manifold pressure, which is indicative of engine power produced.
ConvertUnits.com provides an online conversion calculator for all types of measurement units. You can find metric conversion tables for SI units, as well as English units, currency, and other data. Type in unit symbols, abbreviations, or full names for units of length, area, mass, pressure, and other types. Examples include mm, inch, 70 kg, 150 lbs, US fluid ounce, 6'3", 10 stone 4, cubic cm, metres squared, grams, moles, feet per second, and many more!